This is a central location for the definitions available for many of the technical or medical words found on this site. Please click on the letters below to find definitions for words starting with that letter.
When you see these icons you may click on them for: Definition Pronunciation

Special thanks to the National Cancer Institute (NCI). Many of the definitions in this glossary were adapted or taken directly from the NCI's Dictionary of Cancer Terms.

ABCDEFGHIJKLMNOPQRSTUVWXYZ

abdomen (AB-do-men)
The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

abdominal
Having to do with the abdomen, which is the part of the body between the chest and the hips that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

abdominal x-ray
An x-ray of the organs inside the abdomen. An x-ray is a type of radiation that can pass through the body and onto film, making pictures of areas inside the body. X-rays may be used to help diagnose disease.

ablation
In medicine, the removal or destruction of a body part or tissue or its function. Ablation may be performed by surgery, hormones, drugs, radiofrequency, heat, or other methods.

abnormal
Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

abscess
An enclosed collection of pus in tissues, organs, or confined spaces in the body. An abscess is a sign of infection and is usually swollen and inflamed.

absorption (ub-SORP-shun)
The process of taking nutrients from the digestive system into the blood so they can be used in the body.

acetaminophen
A drug that reduces pain and fever (but not inflammation). It belongs to the family of drugs called analgesics.

acne
A disorder of the skin in which oil glands and hair glands become inflamed.

action study
In cancer prevention clinical trials, a study that focuses on finding out whether actions people take can prevent cancer.

activities of daily living
ADL. The tasks of everyday life. Basic ADLs include eating, dressing, getting into or out of a bed or chair, taking a bath or shower, and using the toilet. Instrumental activities of daily living (IADL) are activities related to independent living and include preparing meals, managing money, shopping, doing housework, and using a telephone.

Actos
A drug that is used to treat type 2 diabetes and is being studied in the prevention of head and neck cancer. It may be able to stop leukoplakia (a precancerous condition affecting the mouth) from developing into cancer. It belongs to the family of drugs called thiazolidinediones. Also called pioglitazone.

acupoint (AK-yoo-poynt)
A specific spot on the body where an acupuncture needle may be inserted to control pain and other symptoms. Also called an acupuncture point.

acupressure (AK-yoo-PRESH-er)
The application of pressure or localized massage to specific sites on the body to control symptoms such as pain or nausea. It is a type of complementary and alternative medicine.

acupuncture (AK-yoo-PUNK-chur)
The technique of inserting thin needles through the skin at specific points on the body to control pain and other symptoms. It is a type of complementary and alternative medicine.

acupuncture needle (AK-yoo-PUNK-chur NEE-dul)
A stainless steel needle that is slightly thicker than a human hair. Acupuncture needles are inserted through the skin at specific points on the body to control pain and other symptoms.

acupuncture point (AK-yoo-PUNK-chur poynt)
A specific spot on the body where an acupuncture needle may be inserted to control pain and other symptoms. Also called an acupoint.

acupuncture point injection
(AK-yoo-PUNK-cher poynt in-JEK-shun)

A procedure in which drugs, vitamins, herbal extracts, or other fluids are injected into the body at an acupuncture point using a syringe and needle.

acustimulation
Mild electrical stimulation of acupuncture points to control symptoms such as nausea and vomiting.

acute
Symptoms or signs that begin and worsen quickly; not chronic.

acute pain
Pain that comes on quickly, can be severe, but lasts a relatively short time.

addiction
Uncontrollable craving, seeking, and use of a substance such as a drug or alcohol.

adenocarcinoma (AD-in-o-KAR-sih-NOH-muh)
Cancer that begins in cells that line certain internal organs and that have glandular (secretory) properties.

adenoma (ad-in-O-ma)
A noncancerous tumor.

adenopathy (ad-en-OP-a-thee)
Large or swollen lymph glands.

adenovirus
A group of viruses that cause respiratory tract and eye infections. Adenoviruses used in gene therapy are altered to carry a specific tumor-fighting gene.

adjunct agent
In cancer therapy, a drug or substance used in addition to the primary therapy.

adjunct therapy (A-junkt THAYR-uh-pee)
Another treatment used together with the primary treatment. Its purpose is to assist the primary treatment. Also called adjunctive therapy.

adjunctive therapy
Another treatment used together with the primary treatment. Its purpose is to assist the primary treatment. Also called adjunct therapy.

adjuvant therapy (AD-joo-vant)
Treatment given after the primary treatment to increase the chances of a cure. Adjuvant therapy may include chemotherapy, radiation therapy, hormone therapy, or biological therapy.

ADL
Activities of daily living. The tasks of everyday life. Basic ADLs include eating, dressing, getting into or out of a bed or chair, taking a bath or shower, and using the toilet. Instrumental activities of daily living (IADL) are activities related to independent living and include preparing meals, managing money, shopping, doing housework, and using a telephone.

advance directive
A legal document that states the treatment or care a person wishes to receive or not receive if he or she becomes unable to make medical decisions (for example, due to being unconscious or in a coma). Some types of advance directives are living wills and do-not-resuscitate (DNR) orders.

adverse effect
An unwanted side effect of treatment.

adverse event (AD-vers eh-VENT)
An unexpected medical problem that happens during treatment with a drug or other therapy. Adverse events do not have to be caused by the drug or therapy, and they may be mild, moderate, or severe.

agent study
In cancer prevention clinical trials, a study that tests whether taking certain medicines, vitamins, minerals, or food supplements can prevent cancer. Also a called chemoprevention study.

aggressive
A quickly growing cancer.

Aggressive communication
Includes attacking, blaming, or attempting to manipulate the listener into feeling responsible or guilty.

agonist
A drug that triggers an action from a cell or another drug.

AJCC staging system
A system developed by the American Joint Committee on Cancer for describing the extent of cancer in a patient’s body. The descriptions include TNM: T describes the size of the tumor and if it has invaded nearby tissue, N describes any lymph nodes that are involved, and M describes metastasis (spread of cancer from one body part to another).

alcoholism (AL-kuh-HAW-LIH-zum)
A disease in which a person craves alcohol, is unable to limit his or her drinking, needs to drink greater amounts to get the same effect, and has withdrawal symptoms after stopping alcohol use. Alcoholism affects physical and mental health, and causes problems with family, friends, and work. Also called alcohol dependence.

allergen (AL-er-jen)
A substance that causes an allergic response. Examples include pollen, molds, and certain foods.

allergic response (uh-LER-jik...)
A hypersensitive immune reaction to a substance that normally is harmless or would not cause an immune response in everyone. An allergic response may cause harmful symptoms such as itching or inflammation or tissue injury.

allogeneic (Al-o-jen-AY-ik)
Taken from different individuals of the same species. Also called allogenic.

allogenic
Taken from different individuals of the same species. Also called allogeneic.

allopathic medicine
A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery. Also called conventional medicine, Western medicine, mainstream medicine, orthodox medicine, and biomedicine.

alopecia (al-oh-PEE-shuh)
The lack or loss of hair from areas of the body where hair is usually found. Alopecia can be a side effect of some cancer treatments.

alternative medicine
Practices used instead of standard treatments. They generally are not recognized by the medical community as standard or conventional medical approaches. Alternative medicine includes dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

analgesia (AN-ul-JEE-zee-uh)
Pain relief.

analgesic
A drug that reduces pain. Analgesics include aspirin, acetaminophen, and ibuprofen.

analog
In chemistry, a substance that is similar, but not identical, to another.

analysis
A process in which anything complex is separated into simple or less complex parts.

anaphylactic shock
A severe and sometimes life-threatening immune system reaction to an antigen that a person has been previously exposed to. The reaction may include itchy skin, edema, collapsed blood vessels, fainting, and difficulty in breathing.

anaplastic (an-ah-PLAS-tik)
A term used to describe cancer cells that divide rapidly and have little or no resemblance to normal cells.

anatomy (uh-NA-tuh-mee)
The study of the structure of a plant or animal.

anemia (a-NEE-mee-a)
A condition in which the number of red blood cells is below normal.

anesthesia (an-es-THEE-zha)
Drugs or substances that cause loss of feeling or awareness. Local anesthetics cause loss of feeling in a part of the body. General anesthetics put the person to sleep.

anesthesiologist
A doctor who specializes in giving drugs or other agents to prevent or relieve pain during surgery or other procedures being done in the hospital.

anesthetic (an-es-THET-ik)
A substance that causes loss of feeling or awareness. Local anesthetics cause loss of feeling in a part of the body. General anesthetics put the person to sleep.

angelica root (an-JEH-lih-kuh root)
The root of any of a group of herbs called Angelica. It has been used in some cultures to treat certain medical problems, including gastrointestinal problems such as loss of appetite, feelings of fullness, and gas.

angiogenesis (AN-jee-oh-JEN-eh-sis)
Blood vessel formation. Tumor angiogenesis is the growth of blood vessels from surrounding tissue to a solid tumor. This is caused by the release of chemicals by the tumor.

angiogenesis inhibitor
A substance that may prevent the formation of blood vessels. In anticancer therapy, an angiogenesis inhibitor prevents the growth of blood vessels from surrounding tissue to a solid tumor.

animal model
An animal with a disease either the same as or like a disease in humans. Animal models are used to study the development and progression of diseases and to test new treatments before they are given to humans. Animals with transplanted human cancers or other tissues are called xenograft models.

animal study (AN-ih-mul STUH-dee)
A laboratory experiment using animals to study the development and progression of diseases. Animal studies also test how safe and effective new treatments are before they are tested in people.

anorexia
An abnormal loss of the appetite for food. Anorexia can be caused by cancer, AIDS, a mental disorder (i.e., anorexia nervosa), or other diseases.

anorexia nervosa
An eating disorder marked by an intense fear of gaining weight, a refusal to maintain a healthy weight, and a distorted body image. People with anorexia nervosa have an abnormal loss of appetite for food, try to avoid eating, and eat as little as possible.

antagonist
In medicine, a substance that stops the action or effect of another substance. For example, a drug that blocks the stimulating effect of estrogen on a tumor cell is called an estrogen receptor antagonist.

anterior (an-TEER-ee-er)
In human anatomy, has to do with the front of a structure, or a structure found toward the front of the body.

antibiotic (an-tih-by-AH-tik)
A drug used to treat infections caused by bacteria and other microorganisms.

antibody (AN-tih-BAH-dee)
A type of protein made by plasma cells (a type of white blood cell) in response to an antigen (foreign substance). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.

antibody therapy
Treatment with an antibody, a substance that can directly kill specific tumor cells or stimulate the immune system to kill tumor cells.

anticachexia (AN-tee-ka-KEK-see-a)
Describes a drug or effect that works against cachexia (loss of body weight and muscle mass).

anticancer antibiotic
A type of anticancer drug that blocks cell growth by interfering with DNA, the genetic material in cells. Also called an antitumor antibiotic or antineoplastic antibiotic.

anticarcinogenic (AN-tee-KAR-sin-o-JEN-ik)
Having to do with preventing or delaying the development of cancer.

anticoagulant
A drug that helps prevent blood clots from forming. Also called a blood thinner.

anticonvulsant (AN-tee-kon-VUL-sant)
A drug or other substance used to prevent or stop seizures or convulsions. Also called an antiepileptic.

antidepressant
A drug used to treat depression.

antiemetic (AN-tee-eh-MEH-tik)
A drug that prevents or reduces nausea and vomiting.

antiepileptic (AN-tee-EH-pih-LEP-tik)
A drug or other substance used to prevent or stop seizures or convulsions. Also called an anticonvulsant.

antiestrogen
A substance that blocks the activity of estrogens, the family of hormones that promote the development and maintenance of female sex characteristics.

antimitotic agent
A drug that inhibits cell growth by stopping cell division. Antimitotic agents are used as treatments for cancer. Also called antimicrotubule agents, mitotic inhibitors, and taxanes. Docetaxel and paclitaxel are antimitotic agents.

antineoplastic
A substance that blocks the formation of neoplasms (growths that may become cancerous).

antineoplastic antibiotic
A type of anticancer drug that blocks cell growth by interfering with DNA, the genetic material in cells. Also called an anticancer antibiotic or antitumor antibiotic.

antioxidant (an-tee-OKS-i-dent)
A substance that prevents damage caused by free radicals. Free radicals are highly reactive chemicals that often contain oxygen. They are produced when molecules are split to give products that have unpaired electrons. This process is called oxidation.

anxiety (ang-ZY-uh-tee)
Feelings of fear, dread, and uneasiness that may occur as a reaction to stress. A person with anxiety may sweat, feel restless and tense, and have a rapid heart beat. Extreme anxiety that happens often over time may be a sign of an anxiety disorder.

apheresis
A procedure in which blood is collected, part of the blood such as platelets or white blood cells is taken out, and the rest of the blood is returned to the donor. Also called pheresis.

apoptosis (AY-pup-TOE-siss)
A type of cell death in which a series of molecular steps in a cell leads to its death. This is the body’s normal way of getting rid of unneeded or abnormal cells. The process of apoptosis may be blocked in cancer cells. Also called programmed cell death.

areola (a-REE-o-la)
The area of dark-colored skin on the breast that surrounds the nipple.

artery (AR-tuh-ree)
A blood vessel that carries blood from the heart to tissues and organs in the body.

arthritis
A disease that causes inflammation and pain in the joints.

ascorbic acid (a-SKOR-bik ASS-id)
A key nutrient that the body needs to fight infection, heal wounds, and keep tissues healthy, including the blood vessels, cartilage, ligaments, tendons, bones, muscle, skin, teeth, and gums. It is an antioxidant that helps prevent tissue damage caused by free radicals. The body does not make or store ascorbic acid, so it must be taken in every day. It is found in many fruits and vegetables, especially green peppers, citrus, strawberries, tomatoes, broccoli, leafy greens, potatoes, and cantaloupe. Also called vitamin C.

aspirin
A drug that reduces pain, fever, inflammation, and blood clotting. Aspirin belongs to the family of drugs called nonsteroidal anti-inflammatory agents. It is also being studied in cancer prevention.

assay (AS-say)
A laboratory test to find and measure the amount of a specific substance.

Assertive communication
A clear and firm, but not aggressive way to explain your problem.

assessment (uh-SESS-ment)
In healthcare, a process used to learn about a patient’s condition. This may include a complete medical history, medical tests, a physical exam, a test of learning skills, tests to find out if the patient is able to carry out the tasks of daily living, a mental health evaluation, and a review of social support and community resources available to the patient.

asthenia
Weakness; lack of energy and strength.

asthma (AZ-muh)
A chronic disease in which the bronchial airways in the lungs become narrowed and swollen, making it difficult to breathe. Symptoms include wheezing, coughing, tightness in the chest, shortness of breath, and rapid breathing. An attack may be brought on by pet hair, dust, smoke, pollen, mold, exercise, cold air, or stress.

asymmetry
Lack or absence of balanced proportions between parts of a thing.

asymptomatic
Having no signs or symptoms of disease.

axilla (ak-SIL-a)
The underarm or armpit.

axillary (AK-sil-air-ee)
Pertaining to the armpit area, including the lymph nodes that are located there.

axillary dissection (AK-suh-LAIR-ee dis-EK-shun)
Surgery to remove lymph nodes found in the armpit region. Also called axillary lymph node dissection.

axillary lymph node (AK-suh-LAIR-ee)
A lymph node in the armpit region that drains lymph channels from the breast.

axillary lymph node dissection (AK-suh-LAIR-ee…dis-EK-shun)
Surgery to remove lymph nodes found in the armpit region. Also called axillary dissection.

ABCDEFGHIJKLMNOPQRSTUVWXYZ

baseline
An initial measurement that is taken at an early time point to represent a beginning condition, and is used for comparison over time to look for changes. For example, the size of a tumor will be measured before treatment (baseline) and then afterwards to see if the treatment had an effect.

basophil
A type of white blood cell. Basophils are granulocytes.

batimastat
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors. Batimastat is a matrix metalloproteinase inhibitor.

BAY 12-9566
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

BAY 43-9006
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called raf kinase inhibitors. Also called sorafenib and Nexavar.

BAY 56-3722
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called camptothecins.

BAY 59-8862
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxanes.

BB-10901
A substance that combines a monoclonal antibody (huN901) with an anticancer drug (DM1), and is being studied in the treatment of certain cancers, including non-small cell lung cancer. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

BBBD
Blood-brain barrier disruption. The use of drugs to create openings between cells in the blood-brain barrier. The blood-brain barrier is a protective network of blood vessels and tissue that protects the brain from harmful substances, but can also prevent anticancer drugs from reaching the brain. Once the barrier is opened, anticancer drugs may be infused into an artery that goes to the brain, in order to treat brain tumors.

BBR 2778
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitumor antibiotics. Also called pixantrone.

BBR 3464
A substance that is being studied in the treatment of cancer. It belongs to the family of platinum-based drugs.

BCG
Bacillus Calmette Guérin. A type of bacteria used in cancer treatment to stimulate the immune system. It is also used to vaccinate against tuberculosis.

BCG solution
A form of biological therapy for superficial bladder cancer. A catheter is used to place the BCG solution into the bladder. The solution contains live, weakened bacteria (bacillus Calmette-Guérin) that activate the immune system. The BCG solution used for bladder cancer is not the same thing as BCG vaccine, a vaccine for tuberculosis.

bcl-2 antisense oligodeoxynucleotide G3139
A substance that is being studied in the treatment of cancer. It may kill cancer cells by blocking the production of a protein that makes cancer cells live longer and by making them more sensitive to anticancer drugs. It belongs to the family of drugs called antisense oligodeoxyribonucleotides. Also called oblimersen, augmerosen, and Genasense.

BCX-1777
A substance that is being studied in the treatment of some types of leukemia and lymphoma. It belongs to the family of drugs called purine nucleoside phosphorylase (PNP) enzyme inhibitors. Also called forodesine.

Beckwith-Wiedemann syndrome
A rare, overgrowth disorder in which babies are large at birth and may develop low blood sugar. Other common symptoms are a large tongue, large internal organs, and defects of the abdominal wall near the navel. Beckwith-Wiedemann syndrome increases the risk of developing certain cancers, especially Wilms’ tumor.

beclomethasone
A drug being studied in the treatment of graft-versus-host disease. It belongs to a family of drugs called corticosteroids.

Bellini duct carcinoma
BDC. A rare type of kidney cancer that grows and spreads quickly. It begins in the duct of Bellini in the kidney.

Bence Jones protein
A small protein made by plasma cells (white blood cells that produce antibodies). It is found in the urine of most people with multiple myeloma (cancer that begins in plasma cells).

bendamustine
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called alkylating agents. Also called SDX-105.

benign (beh-NINE)
Not cancerous. Benign tumors may grow larger but do not spread to other parts of the body.

benign breast disease (bih-NYN brest dih-ZEEZ)
A common condition marked by benign (noncancerous) changes in breast tissue. These changes may include irregular lumps or cysts, breast discomfort, sensitive nipples, and itching. These symptoms may change throughout the menstrual cycle and usually stop after menopause. Also called fibrocystic breast disease, fibrocystic breast changes, and mammary dysplasia.

benign proliferative breast disease
A group of noncancerous conditions that may increase the risk of developing breast cancer. Examples include ductal hyperplasia, lobular hyperplasia, and papillomas.

benign prostatic hyperplasia (beh-NINE prah-STA-tik hy-per-PLAY-zhuh)
BPH. A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy.

benign prostatic hypertrophy (beh-NINE prah-STA-tik HY-per-troh-fee)
BPH. A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hyperplasia.

benign tumor (beh-NINE)
A noncancerous growth that does not invade nearby tissue or spread to other parts of the body.

benzaldehyde
A colorless oily liquid used as a flavoring agent and to make dyes, perfumes, and pharmaceuticals. Benzaldehyde is chemically related to benzene.

benzene
A chemical that is used widely by the chemical industry, and is also found in tobacco smoke, vehicle emissions, and gasoline fumes. Exposure to benzene may increase the risk of developing leukemia.

benzoylphenylurea
BPU. A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitubulin agents.

benzydamine
A substance that is being studied as a mouth rinse treatment for oral mucositis (painful mouth sores) caused by cancer therapy. It belongs to the family of nonsteroidal anti-inflammatory drugs (NSAIDS).

bereavement (beh-REEV-ment)
A state of sadness, grief, and mourning after the loss of a loved one.

Beriplast P
A substance used in surgical wound healing to cause a blood clot to form. It consists of blood-clotting factors found naturally in human blood.

best practice
In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with the best practice. Also called standard therapy or standard of care.

beta alethine
A substance that is being studied in the treatment of cancer. It belongs to a family of chemicals called disulfides.

beta carotene
A vitamin A precursor. Beta carotene belongs to the family of fat-soluble vitamins called carotenoids.

beta hemolytic streptococcus group B
A type of bacteria often found in the vagina. It can cause systemic infections in people with suppressed immune systems.

beta-2-microglobulin (MY-kroh-GLOB-yoo-lin)
A small protein normally found on the surface of many cells, including lymphocytes, and in small amounts in the blood and urine. An increased amount in the blood or urine may be a sign of certain diseases, including some types of cancer, such as multiple myeloma or lymphoma.

beta-endorphin
A substance produced in the brain, especially in the pituitary gland, that blocks the sensation of pain. It is produced in response to pain, exercise, and other forms of stress. It belongs to a group of chemicals called polypeptide hormones.

beta-glucan
A type of polysaccharide (string of sugar molecules) obtained from several types of mushrooms. It is being studied as a treatment for cancer and as an immune system stimulant.

beta-human chorionic gonadotropin
ß-hCG. A hormone normally found in the blood and urine during pregnancy. It may also be produced by some tumor cells. An increased level of ß-hCG may be a sign of cancer of the testis, uterus, ovary, liver, stomach, pancreas, or lung. ß-hCG may also be produced in response to certain conditions that are not cancer. ß-hCG is being studied in the treatment of Kaposi’s sarcoma.

bevacizumab (be-vuh-SIZ-uh-mab)
A monoclonal antibody used in the treatment of colorectal cancer that has spread. It is also being studied in the treatment of other types of cancer. It may prevent the growth of new blood vessels from surrounding tissue to a solid tumor. Also called Avastin.

bexarotene
An anticancer drug used to decrease the growth of some types of cancer cells. It belongs to the family of drugs called retinoids. Also called LGD1069.

Bexxar regimen (BEX-ar REH-jih-men)
A combination of monoclonal antibodies used to treat certain types of non-Hodgkin’s lymphoma. The monoclonal antibody tositumomab is given with iodine I 131 tositumomab (a form of tositumomab that has been chemically changed by adding radioactive iodine). Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

BG00001
A gene therapy agent that is being studied in the treatment of cancer. It belongs to the family of drugs called biological response modifiers.

BI-RADS
Breast Imaging Reporting and Data System. A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis.

Biafine cream
A topical preparation to reduce the risk of, and treat skin reactions to, radiation therapy.

bias
In a clinical trial, a flaw in the study design or method of collecting or interpreting information. Biases can lead to incorrect conclusions about what the study or trial showed.

BIBX 1382
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epidermal growth factor receptor (EGFR) inhibitors.

bicalutamide (bye-ka-LOO-ta-mide)
An anticancer drug that belongs to the family of drugs called antiandrogens.

bidi
A cigarette made by rolling tobacco by hand in a dried leaf from the tendu tree (a member of the ebony family). Most bidis are made in India and they come in different flavors.

bilateral
Affecting both the right and left sides of the body.

bilateral cancer
Cancer that occurs in both paired organs, such as both breasts or both ovaries.

bilateral nephrectomy (by-LAT-uh-ral neh-FREK-tuh-mee)
Surgery to remove both kidneys.

bilateral prophylactic mastectomy (by-LAT-uh-ral pro-fi-LAK-tik mas-TEK-tuh-mee)
Surgery to remove both breasts in order to reduce the risk of developing breast cancer. Also called preventive mastectomy.

bilateral salpingo-oophorectomy
Surgery to remove both ovaries and both fallopian tubes.

bile
A fluid made by the liver and stored in the gallbladder. Bile is excreted into the small intestine, where it helps digest fat.

bile duct
A tube through which bile passes in and out of the liver.

biliary
Having to do with the liver, bile ducts, and/or gallbladder.

bilirubin (bil-ih-ROO-bun)
Substance formed when red blood cells are broken down. Bilirubin is part of the bile, which is made in the liver and is stored in the gallbladder. The abnormal buildup of bilirubin causes jaundice.

binding agent
A substance that makes a loose mixture stick together. For example, binding agents can be used to make solid pills from loose powders.

bioavailable
The ability of a drug or other substance to be absorbed and used by the body. Orally bioavailable means that a drug or other substance that is taken by mouth can be absorbed and used by the body.

biochanin A
An isoflavone found in soy products. Soy isoflavones are being studied to see if they help prevent cancer.

biochemical reactions
In living cells, chemical reactions that help sustain life and allow cells to grow.

biofeedback
A method of learning to voluntarily control certain body functions such as heartbeat, blood pressure, and muscle tension with the help of a special machine. This method can help control pain.

biologic agent
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biologic agents include antibodies, interleukins, and vaccines. Also called biological agent or biological drug.

biological (by-o-LAHJ-i-kul)
Pertaining to biology or to life and living things. In medicine, refers to a substance made from a living organism or its products. Biologicals may be used to prevent, diagnose, treat or relieve of symptoms of a disease. For example, antibodies, interleukins, and vaccines are biologicals. Biological also refers to parents and children who are related by blood.

biological agent
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biological agents include antibodies, interleukins, and vaccines. Also called biologic agent or biological drug.

biological drug
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biological drugs include antibodies, interleukins, and vaccines. Also called biologic agent or biological agent.

biological response modifier therapy (by-oh-LAH-jih-kul...)
BRM therapy. Treatment to stimulate or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by cancer treatment. Also called immunotherapy, biotherapy, or biological therapy.

biological therapy (by-oh-LAH-jih-kul THAYR-uh-pee)
Treatment to stimulate or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by some cancer treatments. Also called immunotherapy, biotherapy, or biological response modifier (BRM) therapy.

biomarker
A substance sometimes found in the blood, other body fluids, or tissues. A high level of biomarker may mean that a certain type of cancer is in the body. Examples of biomarkers include CA 125 (ovarian cancer), CA 15-3 (breast cancer), CEA (ovarian, lung, breast, pancreas, and gastrointestinal tract cancers), and PSA (prostate cancer). Also called tumor marker.

Biomed 101
A substance that is being studied for its ability to decrease the side effects of interleukin-2 (IL-2).

biomedicine
A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery. Also called conventional medicine, Western medicine, mainstream medicine, orthodox medicine, and allopathic medicine.

biopsy (BY-op-see)
The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. When only a sample of tissue is removed, the procedure is called an incisional biopsy. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is called a needle biopsy, core biopsy, or fine-needle aspiration.

biopsy specimen
Tissue removed from the body and examined under a microscope to determine whether disease is present.

biotherapy (by-oh-THAYR-uh-pee)
Treatment to stimulate or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by cancer treatment. Also called biological therapy, immunotherapy, or biological response modifier (BRM) therapy.

Birt-Hogg-Dube syndrome
An inherited condition in which benign tumors develop in hair follicles on the head, chest, back, and arms. People who have this disorder may be at increased risk of developing colon or kidney cancer.

birth control pill
A pill used to prevent pregnancy. It contains hormones that block the release of eggs from the ovaries. Most birth control pills include estrogen and progestin. Also called oral contraceptive pill.

bispecific antibody
An antibody developed in the laboratory to recognize more than one protein on the surface of different cells. Examples include bispecific antibodies 2B1, 520C9xH22, mDX-H210, and MDX447.

bispecific monoclonal antibody
A monoclonal antibody that binds two different types of antigen. Bispecific monoclonal antibodies do not occur naturally; they must be made in the laboratory.

bisphosphonate
A type of drug used to treat osteoporosis and the bone pain caused by some types of cancer. Also called diphosphonate.

bizelesin
An anticancer drug that belongs to the family of drugs called alkylating agents. It is also an antitumor antibiotic.

BL22 immunotoxin
A bacterial toxic substance linked to an antibody that attaches to cancer cells and kills them. It belongs to the family of drugs called bacterial immunotoxins.

black cohosh
Cimicifuga racemosa. An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The plant is also called black snakeroot, rattlesnake root, bugwort, and bugbane.

black snakeroot
Cimicifuga racemosa. An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The plant is also called black cohosh, rattlesnake root, bugwort, and bugbane.

bladder
The organ that stores urine.

bladder cancer (BLA-der KAN-ser)
Cancer that forms in tissues of the bladder (the organ that stores urine). Most bladder cancers are transitional cell carcinomas (cancer that forms in cells in the innermost tissue layer of the bladder). Other types include squamous cell carcinoma (cancer that begins in flat cells lining the inside of the bladder) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids).

blast
An immature blood cell.

blast crisis
A phase of chronic myelogenous leukemia in which tiredness, fever, and an enlarged spleen occur during the blastic phase, when more than 30% of the cells in the blood or bone marrow are blast cells (immature blood cells).

blastic phase chronic myelogenous leukemia
A phase of chronic myelogenous leukemia in which more than 30% of the cells in the blood or bone marrow are blast cells (immature blood cells). When tiredness, fever, and an enlarged spleen occur during the blastic phase, it is called blast crisis.

bleomycin
An anticancer drug that belongs to the family of drugs called antitumor antibiotics.

blessed thistle
Cnicus benedictus. A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems. Blessed thistle may have anti-inflammatory and anticancer effects. Also called St. Benedict's thistle, cardin, holy thistle, and spotted thistle.

blinded study
A type of study in which the patients (single-blinded) or the patients and their doctors (double-blinded) do not know which drug or treatment is being given. The opposite of a blinded study is an open label study.

blood
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

blood cell count
A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called complete blood count (CBC).

blood chemistry study
A procedure in which a sample of blood is examined to measure the amounts of certain substances made in the body. An abnormal amount of a substance can be a sign of disease in the organ or tissue that produces it.

blood pressure (blud PREH-shur)
The force of circulating blood on the walls of the arteries. Blood pressure is taken using two measurements: systolic (measured when the heart beats, when blood pressure is at its highest) and diastolic (measured between heart beats, when blood pressure is at its lowest). Blood pressure is written with the systolic blood pressure first, followed by the diastolic blood pressure (for example 120/80).

blood stasis (blud STAY-sis)
In traditional Chinese medicine, a condition described as slowing or pooling of blood, which may cause pain or other symptoms.

blood thinner
A drug that helps prevent blood clots from forming. Also called an anticoagulant.

blood transfusion
The administration of blood or blood products into a blood vessel.

blood vessel
A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

blood-brain barrier
A network of blood vessels with closely spaced cells that makes it difficult for potentially toxic substances (such as anticancer drugs) to penetrate the blood vessel walls and enter the brain.

blood-brain barrier disruption
BBBD. The use of drugs to create openings between cells in the blood-brain barrier. The blood-brain barrier is a protective network of blood vessels and tissue that protects the brain from harmful substances, but can also prevent anticancer drugs from reaching the brain. Once the barrier is opened, anticancer drugs may be infused into an artery that goes to the brain, in order to treat brain tumors.

BMD
Bone mineral density. A measure of the amount of calcium contained in a certain volume of bone. Calcium gives bones their strength and helps keep them from breaking. Bone density measurements may be used to diagnose osteoporosis, to see how well osteoporosis treatments are working, and to figure out how likely the bones are to break. Also called bone density and bone mass.

BMS-182751
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called platinum analogs. Also called JM 216 and satraplatin.

BMS-184476
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called mitotic inhibitors.

BMS-188797
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxane analogs.

BMS-214662
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called farnesyltransferase inhibitors.

BMS-247550
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epothilone analogs. Also called ixabepilone.

BMS-275291
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called matrix metalloproteinase inhibitors (MMPIs).

BMS-354825
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.

BMS-599626
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.

body image (BAH-dee IH-mij)
The way a person thinks about his or her body and how it looks to others.

bolus
A single dose of drug usually injected into a blood vessel over a short period of time. Also called bolus infusion.

bolus infusion
A single dose of drug usually injected into a blood vessel over a short period of time. Also called bolus.

bone cancer
Primary bone cancer is cancer that forms in cells of the bone. Some types of primary bone cancer are osteosarcoma, Ewing's sarcoma, malignant fibrous histiocytoma, and chondrosarcoma. Secondary bone cancer is cancer that spreads to the bone from another part of the body (such as the prostate, breast, or lung).

bone density (DEN-sih-tee)
A measure of the amount of calcium contained in a certain volume of bone. Calcium gives bones their strength and helps keep them from breaking. Bone density measurements may be used to diagnose osteoporosis, to see how well osteoporosis treatments are working, and to figure out how likely the bones are to break. Also called bone mineral density (BMD) and bone mass.

bone marrow
The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

bone marrow ablation
The destruction of bone marrow using radiation or drugs.

bone marrow aspiration (as-per-AY-shun)
The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope.

bone marrow biopsy (BY-op-see)
The removal of a sample of tissue from the bone marrow with a needle for examination under a microscope.

bone marrow cancer
Cancer that forms in the blood-forming cells of the bone marrow (soft sponge-like tissue in the center of most bones). Bone marrow cancer includes leukemias, multiple myeloma, and others.

bone marrow metastases
Cancer that has spread from the original (primary) tumor to the bone marrow.

bone marrow transplantation (trans-plan-TAY-shun)
A procedure to replace bone marrow that has been destroyed by treatment with high doses of anticancer drugs or radiation. Transplantation may be autologous (an individual's own marrow saved before treatment), allogeneic (marrow donated by someone else), or syngeneic (marrow donated by an identical twin).

bone mass
A measure of the amount of calcium contained in a certain volume of bone. Calcium gives bones their strength and helps keep them from breaking. Bone density measurements may be used to diagnose osteoporosis, to see how well osteoporosis treatments are working, and to figure out how likely the bones are to break. Also called bone density and bone mineral density (BMD).

bone metastases
Cancer that has spread from the original (primary) tumor to the bone.

bone mineral density (DEN-sih-tee)
BMD. A measure of the amount of calcium contained in a certain volume of bone. Calcium gives bones their strength and helps keep them from breaking. Bone density measurements may be used to diagnose osteoporosis, to see how well osteoporosis treatments are working, and to figure out how likely the bones are to break. Also called bone density and bone mass.

bone scan
A technique to create images of bones on a computer screen or on film. A small amount of radioactive material is injected into a blood vessel and travels through the bloodstream; it collects in the bones and is detected by a scanner.

bone-seeking radioisotope
A radioactive substance that is given through a vein, and collects in bone cells and in tumor cells that have spread to the bone. It kills cancer cells by giving off low-level radiation.

booster
In medicine, refers to a vaccination given after a previous vaccination. A booster helps maintain or increase a protective immune response.

borderline personality disorder (BOR-der-LINE PER-suh-NA-lih-tee dis-OR-der)
BPD. A serious mental illness marked by unstable moods, and impulsive behavior. People with BPD have problems with relationships, family and work life, long-term planning, and self-identity. Symptoms include intense bouts of anger, depression, and anxiety that may lead to self-injury or suicide, drug or alcohol abuse, excessive spending, binge eating, or risky sex. A person with BPD who is diagnosed with cancer may be at an increased risk of suicide.

boron neutron capture therapy
A type of radiation therapy. The person is given an intravenous infusion containing the element boron, which concentrates in the tumor cells. The person then receives radiation therapy with atomic particles called neutrons from a small research nuclear reactor. The radiation is absorbed by the boron, killing the tumor cells without harming normal cells.

boronophenylalanine-fructose complex
BPA-F. A substance used in a type of radiation therapy called boron neutron capture therapy. BPA-F is injected into a vein, and becomes concentrated in tumor cells. The patient then receives radiation treatment with atomic particles called neutrons. The neutrons react with the boron in BPA-F, producing radioactive particles that kill the tumor cells without harming normal cells.

bortezomib (bor-TEZ-oh-mib)
A drug that is used to treat multiple myeloma and is being studied in the treatment of other types of cancer. It belongs to the families of drugs called proteosome inhibitors and dipeptidyl boronic acids. Also called Velcade and PS-341.

botanical
Having to do with, or derived from, plants.

bowel (BOW-ul)
The long, tube-shaped organ in the abdomen that completes the process of digestion. The bowel has two parts, the small bowel and the large bowel. Also called the intestine.

bowel function (BOW-ul FUNK-shun)
The way the intestines work in terms of how often there are bowel movements, the ability to control when to have a bowel movement, and whether the stools are hard and dry as in constipation or watery as in diarrhea.

Bowen's disease (BOH-enz)
A skin disease marked by scaly or thickened patches on the skin and often caused by prolonged exposure to arsenic. The patches often occur on sun-exposed areas of the skin and in older, white men. These patches may become malignant (cancerous). Also called precancerous dermatosis or precancerous dermatitis.

BPD
Borderline personality disorder. A serious mental illness marked by unstable moods, and impulsive behavior. People with BPD have problems with relationships, family and work life, long-term planning, and self-identity. Symptoms include intense bouts of anger, depression, and anxiety that may lead to self-injury or suicide, drug or alcohol abuse, excessive spending, binge eating, or risky sex. A person with BPD who is diagnosed with cancer may be at an increased risk of suicide.

BPH
Benign prostatic hypertrophy. A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hyperplasia.

BPU
Benzoylphenylurea. A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitubulin agents.

brachial plexopathy (BRAY-kee-ul pleks-AH-pah-thee)
A condition marked by numbness, tingling, pain, weakness, or limited movement in the arm or hand. It is caused by an impairment of the brachial plexus, a network of nerves that affect the arm and hand.

brachial plexus (BRAY-kee-ul PLEKS-us)
A network of nerves that sends signals from the spine to the arm and hand.

brachytherapy (BRA-kee-THAYR-uh-pee)
A procedure in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called internal radiation, implant radiation, or interstitial radiation therapy.

brain metastasis
Cancer that has spread from the original (primary) tumor to the brain.

brain stem
The part of the brain that is connected to the spinal cord.

brain stem glioma (glee-O-ma)
A tumor located in the part of the brain that connects to the spinal cord (the brain stem). It may grow rapidly or slowly, depending on the grade of the tumor.

brain stem tumor
A tumor in the part of the brain that connects to the spinal cord (the brain stem).

brain tumor
The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous).

BRCA1
A gene on chromosome 17 that normally helps to suppress cell growth. A person who inherits an altered version of the BRCA1 gene has a higher risk of getting breast, ovarian, or prostate cancer.

BRCA2
A gene on chromosome 13 that normally helps to suppress cell growth. A person who inherits an altered version of the BRCA2 gene has a higher risk of getting breast, ovarian, or prostate cancer.

breakthrough pain
Intense increases in pain that occur with rapid onset even when pain-control medication is being used. Breakthrough pain can occur spontaneously or in relation to a specific activity.

breast
Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

breast cancer (brest KAN-ser)
Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

breast cancer in situ
Abnormal cells that are confined to the ducts or lobules in the breast. There are two forms, called ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS).

Breast conserving surgery
"Breast conserving surgery" is sometimes called a "lumpectomy". It is the removal of the lump and a small amount of the tissue surrounding the lump, rather than removing the entire breast. Breast conserving surgery leaves most of the breast tissue as it was (conserving = preserving or protecting the undamaged or unaffected portions of the breast). This type of surgery almost always has to include follow-up treatments with radiation.
breast density
Describes the relative amount of different tissues present in the breast. A dense breast has less fat than glandular and connective tissue. Mammogram films of breasts with higher density are harder to read and interpret than those of less dense breasts.

breast duct endoscopy
A method used to examine the lining of the breast ducts to look for abnormal tissue. A very thin, flexible, lighted tube attached to a camera is inserted through the nipple, and threaded into the breast ducts deep in the breast. Tissue and fluid samples may be removed during the procedure.

Breast Imaging Reporting and Data System
BI-RADS. A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis.

breast implant
A silicone gel-filled or saline-filled sac placed under the chest muscle to restore breast shape.

breast reconstruction
Surgery to rebuild the shape of the breast after a mastectomy.

breast self-exam
An exam by a woman of her breasts to check for lumps or other changes.

breast-conserving surgery
An operation to remove the breast cancer but not the breast itself. Types of breast-conserving surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-sparing surgery.

breast-sparing surgery
An operation to remove the breast cancer but not the breast itself. Types of breast-sparing surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-conserving surgery.

Brief Pain Inventory
A questionnaire used to measure pain.

brivudine
A substance that is being studied in the treatment of infections caused by herpesvirus, including herpes-zoster (shingles). It belongs to the family of drugs called antivirals.

BRM therapy
Biological response modifier therapy. Treatment to stimulate or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by cancer treatment. Also called immunotherapy, biotherapy, or biological therapy.

bromelain
An enzyme found in pineapples that breaks down other proteins, such as collagen and muscle fiber, and has anti-inflammatory properties. It is used as a meat tenderizer in the food industry.

bronchi (BRONK-eye)
The large air passages that lead from the trachea (windpipe) to the lungs.

bronchial
Having to do with the bronchi, which are the larger air passages of the lungs, including those that lead from the trachea (windpipe) to the lungs and those within the lungs.

bronchial adenoma (BRON-kee-ul A-deh-NOH-muh)
Cancer that forms in tissues of the bronchi (large air passages in the lungs including those that lead to the lungs from the windpipe).

bronchiole (BRON-kee-ol)
A tiny branch of air tubes in the lungs.

bronchitis (bron-KYE-tis)
Inflammation (swelling and reddening) of the bronchi.

bronchoscope (BRON-ko-skope)
A thin, lighted tube used to examine the inside of the trachea and bronchi, the air passages that lead to the lungs.

bronchoscopy (bron-KOS-ko-pee)
A procedure in which a thin, lighted tube is inserted through the nose or mouth. This allows examination of the inside of the trachea and bronchi (air passages that lead to the lung), as well as the lung. Bronchoscopy may be used to detect cancer or to perform some treatment procedures.

bronchus
A large air passage that leads from the trachea (windpipe) to the lung.

brostallicin
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called DNA intercalators.

broxuridine
A drug that makes cancer cells more sensitive to radiation and is also used as a diagnostic agent to determine how fast cancer cells grow.

bryostatin 1
A substance that is being studied in the treatment of cancer. It is obtained from a marine organism.

BSH
Sodium borocaptate. A substance used in a type of radiation therapy called boron neutron capture therapy. BSH is injected into a vein and becomes concentrated in tumor cells. The patient then receives radiation treatment with atomic particles called neutrons. The neutrons react with the boron in BSH and make radioactive particles that kill the tumor cells without harming normal cells.

buccal mucosa (BUH-kul myoo-KOH-suh)
The inner lining of the cheeks.

budesonide
A drug used in the treatment of asthma and rhinitis. It is also being studied in the treatment of cancer. Budesonide belongs to the family of drugs called steroids.

bugbane
Cimicifuga racemosa. An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The plant is also called black cohosh, black snakeroot, rattlesnake root, and bugwort.

bugwort
Cimicifuga racemosa. An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The plant is also called black cohosh, black snakeroot, rattlesnake root, and bugbane.

bupropion byoo-PRO-pee-ON
A substance that is used to treat depression, and to help people quit smoking. It belongs to the family of drugs called antidepressants.

burdock
Arctium lappa. A plant whose seeds and root have been used in some cultures to treat certain medical problems. It may have antioxidant effects. Also called lappa and happy major.

Burkitt's leukemia
A rare, fast-growing cancer of the blood. Also called B-cell acute lymphocytic leukemia or B-cell acute lymphoblastic leukemia.

Burkitt's lymphoma
An aggressive (fast-growing) type of B-cell non-Hodgkin's lymphoma that occurs most often in children and young adults. The disease may affect the jaw, central nervous system, bowel, kidneys, ovaries, or other organs. There are three main types of Burkitt’s lymphoma (sporadic, endemic, and immunodeficiency related). Sporadic Burkitt’s lymphoma occurs throughout the world, and endemic Burkitt’s lymphoma occurs in Africa. Immunodeficiency-related Burkitt’s lymphoma is most often seen in AIDS patients.

burr hole
A small opening in the skull made with a surgical drill.

bursitis (ber-SY-tis)
Inflammation (swelling, pain, and warmth) of a bursa. A bursa is a flat, fluid-filled sac found between a bone and a tendon or muscle. It forms a cushion to help the tendon or muscle slide smoothly over the bone. Bursitis may be caused by long-term overuse, trauma, rheumatoid arthritis, gout, or infection. It usually affects the shoulder, knee, elbow, hip, or foot.

ABCDEFGHIJKLMNOPQRSTUVWXYZ


C cell
A type of cell in the thyroid. C cells make calcitonin, a hormone that helps control the calcium level in the blood.

c-erbB-2
The gene that controls cell growth by making the human epidermal growth factor receptor 2. Also called HER2/neu.

c-kit receptor
A protein on the surface of some cells that binds to stem cell factor (a substance that causes certain types of cells to grow). Altered forms of this receptor may be associated with some types of cancer.

CA 19-9 assay
A test that measures the level of CA 19-9 in the blood. CA 19-9 is a tumor marker released into the bloodstream from both cancer cells and normal cells. Higher than normal amounts of CA 19-9 in the blood can be a sign of gallbladder or pancreatic cancer or other conditions.

CA-125
A substance sometimes found in an increased amount in the blood, other body fluids, or tissues and that may suggest the presence of some types of cancer.

CA-125 test
A blood test that measures the level of CA-125, a substance found in blood, other body fluids and some tissues. Increased levels of CA-125 may be a sign of cancer.

cachexia (ka-KEK-see-a)
Loss of body weight and muscle mass, and weakness that may occur in patients with cancer, AIDS, or other chronic diseases.

CAD
Coronary artery disease. A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). CAD is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of CAD is increased by having a family history of CAD before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary heart disease.

cadmium (KAD-me-um)
A metallic element that occurs naturally in tiny amounts in air, water, soil, and food. It is a byproduct of zinc refining, and is used to make batteries, pigments, plastics, alloys, and electroplate. It is also found in cigarette smoke. Exposure to high levels of cadmium may cause certain cancers and other health problems.

calcification
Deposits of calcium in the tissues. Calcification in the breast can be seen on a mammogram, but cannot be detected by touch. There are two types of breast calcification, macrocalcification and microcalcification. Macrocalcifications are large deposits and are usually not related to cancer. Microcalcifications are specks of calcium that may be found in an area of rapidly dividing cells. Many microcalcifications clustered together may be a sign of cancer.

calcitonin
A hormone formed by the C cells of the thyroid gland. It helps maintain a healthy level of calcium in the blood. When the calcium level is too high, calcitonin lowers it.

calcitriol (kal-sih-TREE-ol)
The active form of vitamin D. Calcitriol is formed in the kidneys or made in the laboratory. It is used as a drug to increase calcium levels in the body in order to treat skeletal and tissue-related calcium deficiencies caused by kidney or thyroid disorders.

calcium (KAL-see-um)
A mineral found in teeth, bones, and other body tissues.

calcium carbonate
A mineral taken primarily as a supplement to prevent osteoporosis. It is also being studied for cancer prevention.

calendula ointment (kuh-LEN-dyuh-luh OYNT-ment)
A substance made from the flower of the marigold plant Calendula officinalis. Calendula-based skin products have been used to treat minor cuts, burns, and skin irritation. The products that are available in the United States may not contain the same amount or mixture of ingredients and may not be effective. Another product, Calendula ointment, is being studied in France in the prevention of dermatitis in patients having radiation therapy for breast cancer. The ointment being studied is not available in the United States.

caloric intake
Refers to the number of calories (energy content) consumed.

calorie
A measurement of the energy content of food. The body needs calories as "fuel" to perform all of its functions, such as breathing, circulating the blood, and physical activity. When a person is sick, their body may need extra calories to fight fever or other problems.

CAM
Complementary and alternative medicine. Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

Campath-1H
A monoclonal antibody used to treat leukemia. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells. Also called alemtuzumab.

camphor
A substance that comes from the wood and bark of the camphor tree or is made in the laboratory. It has a very unique smell and taste and is used in commercial products (for example, mothballs). Camphor is used in topical anti-infective and anti-pruritic (anti-itching) agents.

camptothecin
An anticancer drug that belongs to the family of drugs called topoisomerase inhibitors.

camptothecin analog
An anticancer drug related in structure to camptothecin, a topoisomerase inhibitor. One such drug is aminocamptothecin.

Cancell (kan-SEL)
A liquid that has been promoted as a treatment for a wide range of diseases, including cancer. The ingredients thought to be in Cancell have been tested, and none of them has been shown to be effective in treating any form of cancer. Cancell is not available in the United States. Also called Entelev, Sheridan's Formula, Jim's Juice, Crocinic Acid, JS'114, JS'101, 126'F, and Cantron.

cancer
A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the bloodstream. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system.

cancer cluster (KAN-ser KLUS-ter)
The occurrence of a larger-than-expected number of cases of cancer within a group of people in a geographic area over a period of time.

Cancer Information Service
CIS. The Cancer Information Service is the National Cancer Institute's link to the public, interpreting and explaining research findings in a clear and understandable manner, and providing personalized responses to specific questions about cancer. Access the CIS by calling 1-800-4-CANCER (1-800-422-6237), or by using the LiveHelp instant-messaging service at https://cissecure.nci.nih.gov/livehelp/welcome.asp.

cancer of the adrenal cortex
A rare cancer that forms in the outer layer of tissue of the adrenal gland (a small organ on top of each kidney that makes steroid hormones, adrenaline, and noradrenaline to control heart rate, blood pressure, and other body functions). Also called adrenocortical cancer and adrenocortical carcinoma.

cancer of unknown primary origin
A case in which cancer cells are found in the body, but the place where the cells first started growing (the origin or primary site) cannot be determined.

cancer vaccine
A vaccine designed to prevent or treat cancer.

candidiasis (kan-dih-DY-uh-siss)
A condition in which Candida albicans, a type of yeast, grows out of control in moist skin areas of the body. It is usually a result of a weakened immune system, but can be a side effect of chemotherapy or treatment with antibiotics. Thrush usually affects the mouth (oral thrush); however, rarely, it spreads throughout the entire body. Also called candidosis or thrush.

candidosis (kan-dih-DOH-siss)
A condition in which Candida albicans, a type of yeast, grows out of control in moist skin areas of the body. It is usually a result of a weakened immune system, but can be a side effect of chemotherapy or treatment with antibiotics. Thrush usually affects the mouth (oral thrush); however, rarely, it spreads throughout the entire body. Also called candidiasis or thrush.

Cantron
A liquid that has been promoted as a treatment for a wide range of diseases, including cancer. The ingredients thought to be in Cantron have been tested, and none of them has been shown to be effective in treating any form of cancer. Cantron is not available in the United States. Also called Entelev, Sheridan's Formula, Jim's Juice, Crocinic Acid, JS'114, JS'101, 126'F, and Cancell.

CAP-1
Carcinoembryonic antigen peptide-1. A protein that can stimulate an immune response.

capecitabine
A drug that is used in the treatment of cancer. It belongs to the family of drugs called antimetabolites.

capillary
The smallest type of blood vessel. A capillary connects an arteriole (small artery) to a venule (small vein) to form a network of blood vessels in almost all parts of the body. The wall of a capillary is thin and leaky, and capillaries are involved in the exchange of fluids and gases between tissues and the blood.

capillary leak syndrome
A condition in which fluid and proteins leak out of tiny blood vessels and flow into surrounding tissues, resulting in dangerously low blood pressure. Capillary leak syndrome may lead to multiple organ failure and shock.

capsaicin
A component of certain plants, including cayenne and red pepper, used topically for peripheral nerve pain. Also being studied for controlling mucositis pain after chemotherapy and radiation therapy.

capsule (KAP-sool)
In medicine, a sac of tissue and blood vessels that surrounds an organ, joint, or tumor. A capsule is also a form for medicine that is taken by mouth. It usually has a shell made of gelatin with the medicine inside.

captopril
A drug used to treat high blood pressure that is also being studied in the prevention of side effects caused by radiation therapy used in the treatment of cancer. It belongs to the family of drugs called ACE inhibitors.

carbendazim
An anticancer drug that belongs to the family of drugs called antifungal agents.

carbogen
An inhalant of oxygen and carbon dioxide that increases the sensitivity of tumor cells to the effects of radiation therapy.

carbohydrate
A sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as starch, chitin or cellulose).

carbolic acid (kar-BAH-lik...)
A very poisonous chemical substance made from tar and also found in some plants and essential oils (scented liquid taken from plants). Carbolic acid is used to make plastics, nylon, epoxy, medicines, and to kill germs. Also called phenol.

carbon-11 acetate
A radioactive form of carbon that is used in positron emission tomography (PET) scanning.

carboplatin
An anticancer drug that belongs to the family of drugs called platinum compounds.

carboxyamidotriazole
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

carboxypeptidase-G2
A bacterial enzyme that is used to neutralize the toxic effects of methotrexate. It belongs to the family of drugs called chemoprotective agents.

carcinoembryonic antigen (KAR-sin-o-EM-bree-ON-ik ANT-i-jun)
CEA. A substance that is sometimes found in an increased amount in the blood of people who have certain cancers, other diseases, or who smoke. It is used as a tumor marker for colorectal cancer.

carcinoembryonic antigen peptide-1
CAP-1. A protein that can stimulate an immune response to certain tumors.

carcinogen (kar-SIN-o-jin)
Any substance that causes cancer.

carcinogenesis
The process by which normal cells are transformed into cancer cells.

carcinoid (KAR-sin-oyd)
A slow-growing type of tumor usually found in the gastrointestinal system (most often in the appendix), and sometimes in the lungs or other sites. Carcinoid tumors may spread to the liver or other sites in the body, and they may secrete substances such as serotonin or prostaglandins, causing carcinoid syndrome.

carcinoid syndrome (KAR-sin-oyd)
A combination of symptoms caused by the release of serotonin and other substances from carcinoid tumors of the gastrointestinal tract. Symptoms may include flushing of the face, flat angiomas (small collections of dilated blood vessels) of the skin, diarrhea, bronchial spasms, rapid pulse, and sudden drops in blood pressure.

carcinoma (KAR-sih-NOH-muh)
Cancer that begins in the skin or in tissues that line or cover internal organs.

carcinoma in situ (KAR-sih-NOH-muh in SYE-too)
Cancer that involves only cells in the tissue in which it began and that has not spread to nearby tissues.

carcinomatosis
A condition in which cancer is spread widely throughout the body, or, in some cases, to a relatively large region of the body. Also called carcinosis.

carcinosarcoma
A malignant tumor that is a mixture of carcinoma (cancer of epithelial tissue, which is skin and tissue that lines or covers the internal organs) and sarcoma (cancer of connective tissue, such as bone, cartilage, and fat).

carcinosis
A condition in which cancer is spread widely throughout the body, or, in some cases, to a relatively large region of the body. Also called carcinomatosis.

carcinostatic (KAR-sin-o-STAT-ik)
Pertaining to slowing or stopping the growth of cancer.

cardiac
Having to do with the heart.

cardiac sarcoma
A rare cancer that develops in tissues of the heart. Also called heart cancer.

cardin
Cnicus benedictus. A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems. Cardin may have anti-inflammatory and anticancer effects. Also called blessed thistle, St. Benedict's thistle, holy thistle, and spotted thistle.

cardiopulmonary
Having to do with the heart and lungs.

cardiotoxicity
Toxicity that affects the heart.

cardiovascular
Having to do with the heart and blood vessels.

carmustine
An anticancer drug that belongs to the family of drugs called alkylating agents.

carnitine
A substance made in the muscles and liver, and also found in certain foods such as meat, poultry, fish, and some dairy products. The body needs carnitine to make energy from fat.

carotenoid
A substance found in yellow and orange fruits and vegetables and in dark green, leafy vegetables. Carotenoids may reduce the risk of developing cancer.

carotid artery (kuh-RAH-tid AR-tuh-ree)
A major artery that carries blood from the heart to the head. There is a carotid artery on each side of the neck, and each one splits into two branches. The interior branch carries blood to the brain and eyes, and the exterior branch carries blood to the face, tongue, and outside parts of the head.

carrier oil (KAYR-ee-er...)
A vegetable or nut oil with little or no scent that is used to dilute or 'carry' essential oils (scented liquid taken from plants).

cartilage (KAR-tih-lij)
A tough, flexible tissue that lines joints and gives structure to the nose, ears, larynx, and other parts of the body.

carzelesin
An anticancer drug that belongs to the family of drugs called alkylating agents.

case report
A detailed report of the diagnosis, treatment, and follow-up of an individual patient. Case reports also contain some demographic information about the patient (for example, age, gender, ethnic origin).

case series
A group or series of case reports involving patients who were given similar treatment. Reports of case series usually contain detailed information about the individual patients. This includes demographic information (for example, age, gender, ethnic origin) and information on diagnosis, treatment, response to treatment, and follow-up after treatment.

case-control study
A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not. Also called a retrospective study.

caspofungin acetate
A drug used to prevent or treat infections caused by a fungus (a type of microorganism). It belongs to the family of drugs called antifungal agents.

Castleman's disease
A rare disorder in which noncancerous growths develop in lymph node tissue.

castration
Removal or destruction of the testicles or ovaries using radiation, surgery, or drugs. Medical castration refers to the use of drugs to suppress the function of the ovaries or testicles.

CAT scan
Computerized axial tomography scan. A series of detailed pictures of areas inside the body, taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computed tomography (CT scan) or computerized tomography.

cataract (KA-tuh-RAKT)
A condition in which the lens of the eye becomes cloudy. Symptoms include blurred, cloudy, or double vision; sensitivity to light; and difficulty seeing at night. Without treatment, cataracts can cause blindness. There are many different types and causes of cataracts. They may occur in people of all ages, but are most common in the elderly.

catechol
A chemical originally isolated from a type of mimosa tree. Catechol is used as an astringent, an antiseptic, and in photography, electroplating, and making other chemicals. It can also be man-made.

catheter (KATH-i-ter)
A flexible tube used to deliver fluids into or withdraw fluids from the body.

cauterization (KAW-ter-ih-ZAY-shun)
The destruction of tissue with a hot instrument, an electrical current, or a caustic substance.

cauterize (KOT-uh-rize)
To destroy tissue with a hot instrument, an electrical current, or a caustic substance. This process may be used to kill certain types of small tumors or to seal off blood vessels to stop bleeding.

cavity (KA-vih-tee)
A hole in a tooth caused by decay from bacteria in the mouth.

CBC
Complete blood count. A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called blood cell count.

cBR96-doxorubicin immunoconjugate
A substance that is being studied in the treatment of cancer. It combines a monoclonal antibody with the anticancer drug doxorubicin. Monoclonal antibodies are substances that are made in the laboratory and that can locate and bind to cancer cells. cBR96-doxorubicin immunoconjugate belongs to the family of drugs called antibody drug conjugates. Also called SGN-15.

CC-1088
A drug that is being studied in the treatment of cancer. It is similar but not identical to thalidomide. CC-1088 belongs to the family of drugs called angiogenesis inhibitors.

CC-49
A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

CC-5013
A substance that is being studied in the treatment of cancer. It is similar to thalidomide. It belongs to the family of drugs called angiogenesis inhibitors. Also called lenalidomide.

CC-8490
A substance that is being studied in the treatment of brain cancer. It belongs to the family of drugs called benzopyrans.

CC49-streptavidin
A substance that is being studied in the treatment of cancer. It is made by combining the monoclonal antibody CC49 with a chemical called streptavidin. It can find tumor cells that have the protein TAG-72 on their surface, including colon, prostate, breast, and ovary cancer cells. After CC49-streptavidin binds to cancer cells, a radioactive compound called yttrium Y 90 DOTA-biotin will find those cells and kill them.

CCI-779
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called rapamycin analogs. Also called temsirolimus.

CD34 antigen
A protein found on the surface of some bone marrow and blood cells.

CD40-ligand
A substance that is being studied in the treatment of cancer. It binds to certain immune cells and may suppress cancer growth.

CEA
Carcinoembryonic antigen. A substance that is sometimes found in an increased amount in the blood of people who have certain cancers, other diseases, or who smoke. It is used as a tumor marker for colorectal cancer.

CEA assay
A laboratory test to measure carcinoembryonic antigen (CEA), a substance that is sometimes found in an increased amount in the blood of people who have certain cancers.

cecum (SEE-kum)
A pouch that forms the first part of the large intestine. It connects the small intestine to the colon, which is part of the large intestine.

cedarwood (SEE-der-WOOD)
A type of evergreen tree with hard fragrant wood that is a member of the cypress family. The oil from the wood is used in soaps, shampoos, bath salts, perfumes, aromatherapy, and to keep insects away. It is also called Eastern red cedar and red cedar. The scientific name is Juniperus virginiana.

cefepime
A drug used to treat infection. It belongs to the family of drugs called cephalosporin antibiotics.

cefixime
An antibiotic drug used to treat infection. It belongs to the family of drugs called cephalosporins.

ceftriaxone
A drug used to treat infection. It belongs to the family of drugs called cephalosporin antibiotics.

celecoxib (sel-a-KOX-ib)
A drug that reduces pain. Celecoxib belongs to the family of drugs called nonsteroidal anti-inflammatory agents. It is being studied in the prevention of cancer.

Celexa
A drug used to treat depression. It belongs to the families of drugs called antidepressant agents and selective serotonin reuptake inhibitors (SSRIs). Also called citalopram.

celiac disease
A digestive disease that is caused by an immune response to a protein called gluten, which is found in wheat, rye, barley, and oats. Celiac disease damages the lining of the small intestine and interferes with the absorption of nutrients from food. A person with celiac disease may become malnourished no matter how much food is consumed.

cell
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

cell differentiation
The process during which young, immature (unspecialized) cells take on individual characteristics and reach their mature (specialized) form and function.

cell motility
The ability of a cell to move.

cell proliferation
An increase in the number of cells as a result of cell growth and cell division.

cell respiration
A chemical process in which oxygen is used to make energy from carbohydrates (sugars). Also called oxidative metabolism, aerobic metabolism, or aerobic respiration.

cell-cycle regulation
Any process that controls the series of events by which a cell goes through the cell cycle. During the cell cycle, a cell makes a copy of its DNA and other contents, and divides in two. When cell cycle regulation doesn't happen correctly, cells may divide in an uncontrolled way, and diseases such as cancer can occur.

cell-to-cell signaling
The transfer of information from one cell to another.

cellular adhesion
The close adherence (bonding) to adjoining cell surfaces.

cellular adoptive immunotherapy
A treatment used to help the immune system fight cancer. A cancer patient's T cells (a type of white blood cell) are collected and grown in the laboratory to increase the number of T cells that are able to kill the person's cancer cells. These cancer-specific T cells are given back to the patient to help the immune system fight the cancer.

cellular metabolism
The sum of all chemical changes that take place in a cell through which energy and basic components are provided for essential processes, including the synthesis of new molecules and the breakdown and removal of others.

cellulitis
An acute, spreading infection of the deep tissues of the skin and muscle that causes the skin to become warm and tender and may also cause fever, chills, swollen lymph nodes, and blisters.

centimeter
A measure of length in the metric system. A centimeter is one hundredth of a meter. There are 21'2 centimeters in an inch.

central nervous system
CNS. The brain and spinal cord.

central nervous system metastasis (...meh-TAS-ta-sis)
CNS metastasis. Cancer that has spread from the original (primary) tumor to the central nervous system (CNS).

central nervous system primitive neuroectodermal tumor (SEN-trul NER-vuss SISS-tum PRI-muh-tiv NOOR-oh-EK-toh-DER-mul TOO-mer)
CNS PNET. A type of cancer that arises from a particular type of cell within the brain or spinal cord.

central nervous system prophylaxis (...pro-fih-LAK-sis)
CNS prophylaxis. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS sanctuary therapy.

central nervous system sanctuary therapy
CNS sanctuary therapy. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS prophylaxis.

central nervous system tumor
CNS tumor. A tumor of the central nervous system, including brain stem glioma, craniopharyngioma, medulloblastoma, and meningioma.

central venous access catheter
A tube surgically placed into a blood vessel for the purpose of giving intravenous fluid and drugs. It also can be used to obtain blood samples. This device avoids the need for separate needle insertions for each infusion or blood test. Examples of these devices include Hickman catheters, which require clamps to make sure the valve is closed, and Groshong catheters, which have a valve that opens as fluid is withdrawn or infused and remains closed when not in use.

CEP-2563 dihydrochloride
A growth factor antagonist that may stop tumor cells from growing.

CEP-701
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.

cephalexin
An antibiotic drug that belongs to the family of drugs called cephalosporins.

cephalosporin
A drug used to treat bacterial infections. It belongs to the family of drugs called antibiotics.

ceramide
A type of fat produced in the body. It may cause some types of cells to die and is being studied in cancer treatment.

cerebellar hemangioblastoma
A benign, slow-growing tumor in the cerebellum (part of the brain at the back of the head), made up of abnormal blood vessel growth. People with von Hippel-Landau disease have an increased risk of developing hemangioblastomas.

cerebellopontine (SER-uh-BEL-o-PON-teen)
Having to do with two structures of the brain, the cerebellum (located at the lower back of the brain) and the pons (located at the base of the brain in front of the cerebellum) and the area between them.

cerebellum (ser-uh-BEL-um)
The portion of the brain in the back of the head between the cerebrum and the brain stem. The cerebellum controls balance for walking and standing, and other complex motor functions.

cerebral hemisphere (seh-REE-bral HEM-is-feer)
One half of the cerebrum, the part of the brain that controls muscle functions and also controls speech, thought, emotions, reading, writing, and learning. The right hemisphere controls the muscles on the left side of the body, and the left hemisphere controls the muscles on the right side of the body.

cerebrospinal fluid (seh-REE-broe-SPY-nal)
CSF. The fluid flowing around the brain and spinal cord. Cerebrospinal fluid is produced in the ventricles in the brain.

cerebrospinal fluid diversion
A process used to drain fluid that has built up around the brain and spinal cord. A shunt (a long, thin tube) is placed in a ventricle of the brain and threaded under the skin to another part of the body, usually the abdomen. The shunt carries excess fluid away from the brain so it may be absorbed elsewhere in the body.

cerebrum (seh-REE-brum)
The largest part of the brain. It is divided into two hemispheres, or halves, called the cerebral hemispheres. Areas within the cerebrum control muscle functions and also control speech, thought, emotions, reading, writing, and learning.

cervical (SER-vih-kul)
Relating to the neck, or to the neck of any organ or structure. Cervical lymph nodes are located in the neck. Cervical cancer refers to cancer of the uterine cervix, which is the lower, narrow end (the 'neck') of the uterus.

cervical cancer (SER-vih-kul KAN-ser)
Cancer that forms in tissues of the cervix (organ connecting the uterus and vagina). It is usually a slow-growing cancer that may not have symptoms, but can be found with regular Pap smears (procedure in which cells are scraped from the cervix and looked at under a microscope).

cervical intraepithelial neoplasia (SER-vih-kul IN-truh-eh-pih-THEEL-ee-ul NEE-o-play-zha)
CIN. A general term for the growth of abnormal cells on the surface of the cervix. Numbers from 1 to 3 may be used to describe how much of the cervix contains abnormal cells.

cervix (SER-viks)
The lower, narrow end of the uterus that forms a canal between the uterus and vagina.

cetuximab (seh-TUK-sih-mab)
A monoclonal antibody used to treat some types of head and neck cancer, and colorectal cancer that has spread to other parts of the body. It is also being studied in the treatment of other types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. Also called Erbitux.

cevimeline
A substance that increases production of saliva and tears. It is being studied as a treatment for dry mouth caused by radiation therapy to the head and neck. It belongs to the family of drugs called cholinergic enhancers.

CGP 48664
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called S-adenosylmethionine decarboxylase inhibitors.

Chamberlain procedure (CHAYM-ber-len proh-SEE-jer)
A procedure in which a tube is inserted into the chest to view the tissues and organs in the area between the lungs and between the breastbone and heart. The tube is inserted through an incision next to the breastbone. This procedure is usually used to get a tissue sample from the lymph nodes on the left side of the chest. Also called anterior mediastinotomy.

chamomile (KA-moh-MY-ul)
A family of plants with daisy-like flowers that are used in tea to calm and relax, improve sleep, and help digestion.

chaplain (CHA-plin)
A member of the clergy in charge of a chapel or who works with the military or with an institution, such as a hospital.

Chemo
This is a short way to refer to chemotherapy. It is easier to say rather than the whole word and a lot of people use this short version.

Chemo-brain or chemo-fog
Several medications used during chemotherapy can cause problems with your memory. These happen while you are taking chemo and for several months later. In rare cases, some patients have problems with their memory for up to 2 years after they are done with their chemo.

Chemo cocktail
Most chemo treatments include more than one drug. The combination of drugs used together or sometimes referred to as a "cocktail". Your combination of drugs, such as CAF means that you chemo cocktail includes cyclophosphamide (also known as Cytoxan), doxorubicin (also known as Adriamycin), and fluorouracil (also known as 5-FU).

chemoembolization
A procedure in which the blood supply to the tumor is blocked surgically or mechanically and anticancer drugs are administered directly into the tumor. This permits a higher concentration of drug to be in contact with the tumor for a longer period of time.

chemoimmunotherapy
Chemotherapy combined with immunotherapy. Chemotherapy uses different drugs to kill or slow the growth of cancer cells; immunotherapy uses treatments to stimulate or restore the ability of the immune system to fight cancer.

chemoprevention (KEE-mo-pre-VEN-shun)
The use of drugs, vitamins, or other agents to try to reduce the risk of, or delay the development or recurrence of, cancer.

chemoprevention studies
In cancer prevention clinical trials, studies test whether taking certain medicines, vitamins, minerals, or food supplements can prevent cancer. Also called agent studies.

chemoprotective
A quality of some drugs used in cancer treatment. Chemoprotective agents protect healthy tissue from the toxic effects of anticancer drugs.

chemoradiation
Treatment that combines chemotherapy with radiation therapy. Also called chemoradiotherapy.

chemoradiotherapy
Treatment that combines chemotherapy with radiation therapy. Also called chemoradiation.

chemosensitivity
The susceptibility of tumor cells to the cell-killing effects of anticancer drugs.

chemosensitivity assay
A laboratory test that measures the number of tumor cells that are killed by a cancer drug. The test is done after the tumor cells are removed from the body. A chemosensitivity assay may help in choosing the best drug or drugs for the cancer being treated.

chemosensitizer
A drug that makes tumor cells more sensitive to the effects of chemotherapy.

chemotherapeutic agent
A drug used to treat cancer.

chemotherapy (kee-moh-THAYR-uh-pee)
Treatment with drugs that kill cancer cells.

chest wall
The muscles, bones, and joints that make up the area of the body between the neck and the abdomen.

chest x-ray
An x-ray of the structures inside the chest. An x-ray is a type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease.

chiasma (ki-AZ-ma)
An anatomy term for an X-shaped crossing (for example, of nerves or tendons).

child-life worker
A professional who is responsible for making a child's hospital and treatment experience less scary.

Chinese meridian theory (chy-NEEZ meh-RID-ee-un THEER-ee)
In traditional Chinese medicine, meridians are channels that form a network in the body, through which qi (vital energy) flows. Blocked qi causes pain or illness. The flow of qi is restored by using pressure, needles, suction, or heat at hundreds of specific points along the meridians.

Chinese rhubarb
Rheum palmatum or Rheum officinale. The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Also called rhubarb, da-huang, Indian rhubarb, and Turkish rhubarb.

chitin
A type of polysaccharide (sugar molecule) that is made by some plants and animals. The hard outer shell of shrimp, lobsters, and many insects is made of chitin.

chlorambucil
An anticancer drug that belongs to the family of drugs called alkylating agents.

chlorine
A chemical used to disinfect water and as a bleach.

chloroma
A malignant, green-colored tumor of myeloid cells (a type of immature white blood cell). This tumor is usually associated with myelogenous leukemia. Also called granulocytic sarcoma.

chloroquinoxaline sulfonamide
CQS. A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called halogenated sulfanilamides.

cholangiocarcinoma
A rare type of cancer that develops in cells that line the bile ducts in the liver. Cancer that forms where the right and left ducts meet is called Klatskin tumor.

cholangiosarcoma (ko-LAN-jee-o-sar-KO-ma)
A tumor of the connective tissues of the bile ducts.

cholecalciferol (KOH-leh-kal-SIH-fuh-rol)
A nutrient that helps the body use calcium and phosphorus and make strong bones and teeth. It is found in fatty fish, eggs, and dairy products. The skin can also make cholecalciferol when exposed to sunshine. Not getting enough cholecalciferol can cause a bone disease called rickets. Cholecalciferol is being studied in the prevention and treatment of some types of cancer. Also called vitamin D.

cholelith
Solid material that forms in the gallbladder or common bile duct. Choleliths are made of cholesterol or other substances found in the gallbladder. They may occur as one large stone or as many small ones, and vary from the size of a golf ball to a grain of sand. Also called gallstone.

cholestasis
Any condition in which the release of bile from the liver is blocked. The blockage can occur in the liver (intrahepatic cholestasis) or in the bile ducts (extrahepatic cholestasis).

cholesterol (kuh-LESS-tuh-rawl)
A waxy, fat-like substance made in the liver, and found in the blood and in all cells of the body. Cholesterol is important for good health and is needed for making cell walls, tissues, hormones, vitamin D, and bile acid. Cholesterol also comes from eating foods taken from animals such as egg yolks, meat, and whole-milk dairy products. Too much cholesterol in the blood may build up in blood vessel walls, block blood flow to tissues and organs, and increase the risk of developing heart disease and stroke.

chondrocyte
Cartilage cell. Chondrocytes make the structural components of cartilage.

chondroitin sulfate
The major glycosaminoglycan (a type of sugar molecule) in cartilage.

chondrosarcoma (KAHN-dro-sar-KO-ma)
A type of cancer that forms in cartilage.

chordoma (kor-DO-ma)
A type of bone cancer that usually starts in the lower spinal cord.

chorioadenoma destruens
A type of cancer that grows into the muscular wall of the uterus. It is formed after conception (fertilization of an egg by a sperm). It may spread to other parts of the body, such as the vagina, vulva, and lung. Also called invasive hydatidiform mole.

chorioallantoic membrane
The membrane in hen's eggs that helps chicken embryos get enough oxygen and calcium for development. The calcium comes from the egg shell.

choriocarcinoma
A rare cancer in women of childbearing age in which cancer cells grow in the tissues that are formed in the uterus after conception. Also called gestational trophoblastic disease, gestational trophoblastic neoplasia, gestational trophoblastic tumor, or molar pregnancy.

choroid plexus tumor
A rare type of cancer that occurs in the ventricles of the brain. It usually occurs in children younger than 2 years.

CHPP
Continuous hyperthermic peritoneal perfusion. A procedure that bathes the abdominal cavity in fluid that contains anticancer drugs. This fluid is warmer than body temperature. This procedure appears to kill cancer cells without harming normal cells.

chromosome (KRO-mo-some)
Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.

chronic (KRAHN-ik)
A disease or condition that persists or progresses over a long period of time.

chronic eosinophilic leukemia
A disease in which too many eosinophils (a type of white blood cell) are found in the bone marrow, blood, and other tissues. Chronic eosinophilic leukemia may stay the same for many years, or it may progress quickly to acute leukemia.

chronic fatigue syndrome (KRAH-nik fuh-TEEG SIN-drome)
A condition lasting for more than 6 months in which a person feels tired most of the time and may have trouble concentrating and carrying out daily activities. Other symptoms include sore throat, fever, muscle weakness, headache, and joint pain.

chronic granulocytic leukemia
A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myelogenous leukemia or chronic myeloid leukemia.

chronic idiopathic myelofibrosis
A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made in organs such as the liver and the spleen, instead of in the bone marrow. This disease is marked by an enlarged spleen and progressive anemia. Also called agnogenic myeloid metaplasia, primary myelofibrosis, myelosclerosis with myeloid metaplasia, and idiopathic myelofibrosis.

chronic leukemia (KRAHN-ik)
A slowly progressing cancer that starts in blood-forming tissues such as the bone marrow, and causes large numbers of white blood cells to be produced and enter the blood stream.

chronic lymphoblastic leukemia (KRAHN-ik lim-fo-BLAST-ik loo-KEE-mee-a)
A slowly progressing disease in which too many immature white blood cells (called lymphoblasts) are found in the body.

chronic lymphocytic leukemia (KRAHN-ik lim-fo-SIT-ik loo-KEE-mee-a)
CLL. A common type of indolent (slowly progressing) cancer in which too many lymphocytes (white blood cells) are found in the peripheral blood and bone marrow. Most patients with CLL are older than 50 years and have no symptoms at the time of their diagnosis.

chronic myelogenous leukemia (KRAHN-ik mye-eh-LAH-jen-us loo-KEE-mee-a)
CML. A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myeloid leukemia or chronic granulocytic leukemia.

chronic myeloid leukemia (KRAHN-ik MY-eh-loyd loo-KEE-mee-a)
CML. A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myelogenous leukemia or chronic granulocytic leukemia.

chronic myelomonocytic leukemia
CMML. A slowly progressing type of myelodysplastic/myeloproliferative disease in which too many myelomonocytes (a type of white blood cell) are in the bone marrow, crowding out other normal blood cells, such as other white blood cells, red blood cells, and platelets.

chronic neutrophilic leukemia
A disease in which too many neutrophils (a type of white blood cell) are found in the blood. The extra neutrophils may cause the spleen and liver to become enlarged. Chronic neutrophilic leukemia may stay the same for many years or it may progress quickly to acute leukemia.

chronic pain
Pain that can range from mild to severe, and persists or progresses over a long period of time.

chronic phase (KRAHN-ik)
Refers to the early stages of chronic myelogenous leukemia or chronic lymphocytic leukemia. The number of mature and immature abnormal white blood cells in the bone marrow and blood is higher than normal, but lower than in the accelerated or blast phase.

chronic phase chronic myelogenous leukemia
A phase of chronic myelogenous leukemia in which 5% or fewer of the cells in the blood and bone marrow are blast cells (immature blood cells). This phase may last from several months to several years, and there may be no symptoms of leukemia.

CHS 828
A drug that is being studied in the treatment of solid tumors.

CI-1033
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called tyrosine kinase inhibitors.

CI-958
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called DNA-intercalating compounds. Also called sedoxantrone trihydrochloride.

CI-980
An anticancer drug that belongs to the family of drugs called mitotic inhibitors. Also called mivobulin isethionate.

CI-994
A substance that is being studied in the treatment of non-small cell lung cancer. Also called N-acetyldinaline.

cidofovir
A drug used in the treatment of infections caused by viruses.

cilengitide
A substance that is being studied as an anticancer and antiangiogenesis drug. Also called EMD 121974.

cimetidine
A drug usually used to treat stomach ulcers and heartburn. It is also commonly used in a regimen to prevent allergic reactions.

Cipro
A drug used to treat infections caused by bacteria. It is also being studied in the treatment of bladder cancer. Cipro belongs to the family of drugs called fluoroquinolones. Also called ciprofloxacin.

ciprofloxacin (sip-roe-FLOX-a-sin)
A drug used to treat infections caused by bacteria. It is also being studied in the treatment of bladder cancer. Ciprofloxacin belongs to the family of drugs called fluoroquinolones. Also called Cipro.

circulatory system
The system that contains the heart and the blood vessels and moves blood throughout the body. This system helps tissues get enough oxygen and nutrients, and it helps them get rid of waste products. The lymph system, which connects with the blood system, is often considered part of the circulatory system.

circumcision (SUR-kum-SIH-zhun)
Surgery to remove part or all of the foreskin (loose skin that covers the head of the penis).

cirrhosis
A type of chronic, progressive liver disease in which liver cells are replaced by scar tissue.

CIS
Cancer Information Service. The CIS is the National Cancer Institute's link to the public, interpreting and explaining research findings in a clear and understandable manner, and providing personalized responses to specific questions about cancer. Access the CIS by calling 1-800-4-CANCER (1-800-422-6237), or by using the LiveHelp instant-messaging service at https://cissecure.nci.nih.gov/livehelp/welcome.asp.

cisplatin
An anticancer drug that belongs to the family of drugs called platinum compounds.

citalopram (sy-TAL-oh-pram)
A drug used to treat depression. It belongs to the families of drugs called antidepressant agents and selective serotonin reuptake inhibitors (SSRIs). Also called Celexa.

citric acid/potassium-sodium citrate
A drug used in the treatment of metabolic acidosis (a disorder in which the blood is too acidic).

cladribine
An anticancer drug that belongs to the family of drugs called antimetabolites.

clarithromycin
An antibiotic drug used in the treatment of infections. It belongs to the family of drugs called macrolides.

Claus model
A computer program that uses statistics to predict a person's risk for developing breast cancer based on family history.

clavicle
Collar bone.

clear cell
A type of cell that looks clear inside when viewed under a microscope.

clear cell adenocarcinoma
A rare type of tumor, usually of the female genital tract, in which the inside of the cells look clear when viewed under a microscope. Also called clear cell carcinoma and mesonephroma.

clear cell carcinoma (...KAR-sih-NOH-muh)
A rare type of tumor, usually of the female genital tract, in which the inside of the cells look clear when viewed under a microscope. Also called clear cell adenocarcinoma and mesonephroma.

clear cell sarcoma of the kidney
A rare type of kidney cancer. Clear cell sarcoma can spread from the kidney to other organs, most commonly the bone, but also including the lungs, brain, and soft tissues of the body.

cleaved
Having to do with the appearance of cells when viewed under a microscope. The nucleus of cleaved cells appears divided or segmented.

clergy (KLUR-jee)
Ordained individuals who perform spiritual and/or religious functions.

clinical
Having to do with the examination and treatment of patients.

clinical breast exam (CBE)
An exam of the breast performed by a health care provider to check for lumps or other changes.

clinical practice guidelines
Guidelines developed to help health care professionals and patients make decisions about screening, prevention, or treatment of a specific health condition.

clinical resistance
The failure of a cancer to shrink after treatment.

clinical series
A case series in which the patients receive treatment in a clinic or other medical facility.

clinical study
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial.

clinical trial
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical study.

CLL
Chronic lymphocytic leukemia. A common type of indolent (slowly progressing) cancer in which too many lymphocytes (white blood cells) are found in the peripheral blood and bone marrow. Most patients with CLL are older than 50 years and have no symptoms at the time of their diagnosis.

clodronate
A drug used in the treatment of hypercalcemia (abnormally high levels of calcium in the blood) and cancer that has spread to the bone (bone metastases). It may decrease pain, the risk of fractures, and the development of new bone metastases.

clofarabine
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called nucleoside analogs. Also called Clolar.

Clolar
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called nucleoside analogs. Also called clofarabine.

CML
Chronic myelogenous leukemia. A slowly progressing disease in which too many white blood cells are made in the bone marrow. Also called chronic granulocytic leukemia.

CMML
Chronic myelomonocytic leukemia. A slowly progressing type of myelodysplastic/myeloproliferative disease in which too many myelomonocytes (a type of white blood cell) are in the bone marrow, crowding out other normal blood cells, such as other white blood cells, red blood cells, and platelets.

CMV
Cytomegalovirus. A virus that may be carried in an inactive state for life by healthy individuals. It is a cause of severe pneumonia in people with a suppressed immune system, such as those undergoing bone marrow transplantation or those with leukemia or lymphoma.

cnicin
A substance found in certain plants, including blessed thistle. It has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Cnicin belongs to a group of substances called sesquiterpene lactones.

CNS
Central nervous system. The brain and spinal cord.

CNS metastasis (meh-TAS-ta-sis)
Central nervous system metastasis. Cancer that has spread from the original (primary) tumor to the central nervous system (CNS).

CNS PNET
Central nervous system primitive neuroectodermal tumor. A type of cancer that arises from a particular type of cell within the brain or spinal cord.

CNS prophylaxis (pro-fih-LAK-sis)
Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS sanctuary therapy.

CNS sanctuary therapy
Central nervous system sanctuary therapy. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS prophylaxis.

CNS tumor
Central nervous system tumor. A tumor of the central nervous system (CNS), including brain stem glioma, craniopharyngioma, medulloblastoma, and meningioma.

co-culture
A mixture of two or more different kinds of cells that are grown together.

co-trimoxazole
A drug used in the treatment of infections caused by bacteria and protozoa. It is a combination of two anti-infection drugs, sulfamethoxazole and trimethoprim.

coactivated T cell
A T cell that has been coated with monoclonal antibodies to enhance its ability to kill tumor cells.

cobalamin (koh-BAH-luh-min)
A vitamin that is needed to make red blood cells and DNA (the genetic material in cells) and to keep nerve cells healthy. It is found in eggs, meat, poultry, shellfish, milk, and milk products. Cobalamin, along with folate, may be given to help reduce side effects in cancer patients being treated with drugs called antimetabolites. Also called vitamin B12.

cobalt 60
A radioactive form of the metal cobalt, which is used as a source of radiation to treat cancer.

coccyx (KOK-six)
The small bone at the bottom of the spine. It is made up of 3-5 fused bones. Also called the tail bone.

Cockayne syndrome
A genetic condition characterized by short stature, premature aging, sensitivity to light, and possibly deafness and mental retardation.

coenzyme Q10
A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called Q10, CoQ10, vitamin Q10, and ubiquinone.

coffee enema (KAW-fee EH-nuh-muh)
The injection of coffee through the anus into the colon (large intestine). Coffee enemas are being tested in the treatment of pancreatic cancer.

cohort study
A research study that compares a particular outcome (such as lung cancer) in groups of individuals who are alike in many ways but differ by a certain characteristic (for example, female nurses who smoke compared with those who do not smoke).

COL-3
A substance that is being studied in the treatment of cancer. COL-3 may block tumor growth by preventing the growth of new blood vessels into tumors. It belongs to the families of drugs called matrix metalloproteinase inhibitors and angiogenesis inhibitors.

cold nodule
When radioactive material is used to examine the thyroid with a scanner, nodules that collect less radioactive material than the surrounding thyroid tissue are considered "cold." A nodule that is cold does not make thyroid hormone. Cold nodules may be benign or cancerous. Cold nodules are sometimes called hypofunctioning nodules.

colectomy (ko-LEK-tuh-mee)
An operation to remove all or part of the colon. When only part of the colon is removed, it is called a partial colectomy. In an open colectomy, one long incision is made in the wall of the abdomen and doctors can see the colon directly. In a laparoscopic-assisted colectomy, several small incisions are made and a thin, lighted tube attached to a video camera is inserted through one opening to guide the surgery. Surgical instruments are inserted through the other openings to perform the surgery.

colitis
Inflammation of the colon.

collagen
A fibrous protein found in cartilage and other connective tissue.

collagen disease
A term previously used to describe chronic diseases of the connective tissue (e.g., rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis), but now is thought to be more appropriate for diseases associated with defects in collagen, which is a component of the connective tissue.

collagenase
A type of enzyme that breaks down the protein collagen.

collecting duct
The last part of a long, twisting tube that collects urine from the nephrons (cellular structures in the kidney that filter blood and form urine) and moves it into the renal pelvis and ureters. Also called renal collecting tubule.

coloanal anastomosis
A surgical procedure in which the colon is attached to the anus after the rectum has been removed. Also called coloanal pull-through.

coloanal pull-through
A surgical procedure in which the colon is attached to the anus after the rectum has been removed. Also called coloanal anastomosis.

colon (KO-lun)
The longest part of the large intestine, which is a tube-like organ connected to the small intestine at one end and the anus at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.

colon cancer (KO-lun)
Cancer that develops in the tissues of the colon.

colon polyp
An abnormal growth of tissue in the lining of the bowel. Polyps are a risk factor for colon cancer.

colonoscope (koh-LAH-noh-SKOPE)
A thin, tube-like instrument used to examine the inside of the colon. A colonoscope has a light and a lens for viewing and may have a tool to remove tissue.

colonoscopy (KOH-luh-NOSS-koh-pee)
Examination of the inside of the colon using a colonoscope, inserted into the rectum. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.

colony-stimulating factor
A substance that stimulates the production of blood cells. Colony-stimulating factors include granulocyte colony-stimulating factors (also called G-CSF and filgrastim), granulocyte-macrophage colony-stimulating factors (also called GM-CSF and sargramostim), and promegapoietin.

colorectal (ko-lo-REK-tul)
Having to do with the colon or the rectum.

colorectal cancer (KOH-loh-REK-tul KAN-ser)
Cancer that develops in the colon (large intestine) and/or the rectum (the last several inches of the large intestine before the anus).

colostomy (ko-LAHS-toe-mee)
An opening into the colon from the outside of the body. A colostomy provides a new path for waste material to leave the body after part of the colon has been removed.

colposcope (KOL-puh-SKOPE)
A lighted magnifying instrument used to examine the vagina and cervix.

colposcopy (kol-POSS-koh-pee)
Examination of the vagina and cervix using a lighted magnifying instrument called a colposcope.

combination chemotherapy
Treatment using more than one anticancer drug.

combretastatin A4 phosphate
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called tubulin-binding agents.

comedo carcinoma
A type of ductal carcinoma in situ (very early-stage breast cancer).

comfort care
Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of comfort care is to prevent or treat as early as possible the symptoms of the disease, side effects caused by treatment of the disease, and psychological, social, and spiritual problems related to the disease or its treatment. Also called palliative care, supportive care, and symptom management.

common bile duct
Carries bile from the liver and gallbladder into the duodenum (the upper part of the small intestine).


Communication
Includes more than just the words you say. It also includes the tone you use when you say the words and the way you hold your body (body language) when you are saying the words. comorbidity
The condition of having two or more diseases at the same time.

comparative anatomy (kum-PAYR-uh-tiv uh-NA-tuh-mee)
The comparison of the structure (anatomy) of one animal or plant with the structure of a different animal or plant.

compassionate use trial
A way to provide an investigational therapy to a patient who is not eligible to receive that therapy in a clinical trial, but who has a serious or life-threatening illness for which other treatments are not available. Compassionate use allows a patient to receive promising but not yet fully studied or approved cancer therapies when no other treatment option exists. Also called expanded access trial.

complement protein (KOM-pleh-ment PROH-teen)
One of a group of about 20 proteins that is found in the blood and is important in fighting infection and disease.

complementary and alternative medicine
CAM. Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

complementary medicine
Practices often used to enhance or complement standard treatments. They generally are not recognized by the medical community as standard or conventional medical approaches. Complementary medicine may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

complete blood count
CBC. A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called blood cell count.

complete hysterectomy (hiss-ter-EK-toe-mee)
Surgery to remove the entire uterus, including the cervix. Sometimes, not all of the cervix is removed. Also called total hysterectomy.

complete metastasectomy (meh-TAS-ta-SEC-tuh-mee)
Surgery to remove all metastases (tumors formed from cells that have spread from the primary tumor).

complete remission
The disappearance of all signs of cancer in response to treatment. This does not always mean the cancer has been cured. Also called a complete response.

complete response
The disappearance of all signs of cancer in response to treatment. This does not always mean the cancer has been cured. Also called a complete remission.

compliance (kum-PLY-unts)
The act of following a treatment regimen correctly and consistently, including taking medicines and following a diet.

complication (kom-plih-KAY-shun)
In medicine, a medical problem that occurs during a disease, or after a procedure or treatment. The complication may be caused by the disease, procedure, or treatment or may be unrelated to them.

compound (KOM-pownd)
In science, a substance that is made up of more than one ingredient.

compound nevus (KOM-pownd NEE-vus)
A type of mole formed by groups of nevus cells found in the epidermis and dermis (the two main layers of tissue that make up the skin).

compression bandage
A bandage designed to provide pressure to a particular area.

computed tomographic colonography
CTC. A procedure in which a detailed picture of the colon is created by an x-ray machine linked to a computer. Also called computed tomography (CT) scan or computerized axial tomography (CAT) scan of the colon.

computed tomography (tuh-MAH-gra-fee)
CT scan. A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized tomography and computerized axial tomography (CAT) scan.

computed tomography colography
A method under study to examine the colon by taking a series of x-rays (called a CT scan) and using a high-powered computer to reconstruct 2-D and 3-D pictures of the interior surfaces of the colon from these x-rays. The pictures can be saved, manipulated to better viewing angles, and reviewed after the procedure, even years later. Also called virtual colonoscopy.

computerized axial tomography (com-PYEW-ter-ized AX-ee-al tuh-MAH-gra-fee)
A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called CAT scan, computed tomography (CT scan), or computerized tomography.

computerized tomography
A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized axial tomography (CAT) scan and computed tomography (CT scan).

conception (kun-SEP-shun)
In biology, the beginning of pregnancy, marked by fertilization of an egg by a sperm.

concurrent therapy
A treatment that is given at the same time as another.

conditioned stimulus
A situation in which one signal, or stimulus, is given just before another signal. After this happens several times, the first signal alone can cause the response that would usually need the second signal.

condyloma (kahn-dih-LO-ma)
A raised growth on the surface of the genitals caused by human papillomavirus (HPV) infection. The HPV in condyloma is very contagious and can be spread by skin-to-skin contact, usually during oral, anal, or genital sex with an infected partner. A female with condyloma is at an increased risk for developing cervical cancer. Also called genital wart and condylomata acuminata.

condylomata acuminata (kahn-dih-LO-ma-ta a-kyoo-mih-NA-ta)
A raised growth on the surface of the genitals caused by human papillomavirus (HPV) infection. The HPV in condylomata acuminata is very contagious and can be spread by skin-to-skin contact, usually during oral, anal, or genital sex with an infected partner. A female with condylomata acuminata is at an increased risk for developing cervical cancer. Also called condyloma and genital wart.

cone biopsy
Surgery to remove a cone-shaped piece of tissue from the cervix and cervical canal. Cone biopsy may be used to diagnose or treat a cervical condition. Also called conization.

confusion (kun-FYOO-zhun)
A mental state in which one is not thinking clearly.

congestive heart failure
Weakness of the heart muscle that leads to a buildup of fluid in body tissues.

conization (ko-nih-ZAY-shun)
Surgery to remove a cone-shaped piece of tissue from the cervix and cervical canal. Conization may be used to diagnose or treat a cervical condition. Also called cone biopsy.

conjunctiva
A membrane that lines the inner surface of the eyelid and also covers the front part of the eye. Conjunctivitis is inflammation of the conjunctiva.

conjunctivitis
A condition in which the conjunctiva (membranes lining the eyelids and covering the white part of the eye) become inflamed or infected. Also called pinkeye.

connective tissue
Supporting tissue that surrounds other tissues and organs. Specialized connective tissue includes bone, cartilage, blood, and fat.

consecutive case series
A clinical study that includes all eligible patients identified by the researchers during the study registration period. The patients are treated in the order in which they are identified. This type of study usually does not have a control group.

Consensus Development Program
A program of the National Institutes of Health to bring together an independent group of experts to review scientific evidence related to an important public health issue. For a specific issue, a panel of experts (such as doctors and scientists) reviews reports and papers on the subject, listens to information presented by other experts in the field, and hears comments from the general public. Based on the evidence presented, the panel writes a report summarizing the findings, which is made available to the public. The report is not intended to be a practice guideline.

consolidation therapy
A type of high-dose chemotherapy often given as the second phase (after induction therapy) of a cancer treatment regimen for leukemia. Also called intensification therapy.

constipation (KAHN-stih-PAY-shun)
A condition in which stool becomes hard, dry, and difficult to pass, and bowel movements don't happen very often. Other symptoms may include painful bowel movements, and feeling bloated, uncomfortable, and sluggish.

constitutional acupuncture (KON-stih-TOO-shuh-nul AK-yoo-PUNK-cher)
A type of acupuncture based on a form of Oriental medicine in which treatment is based on a person's constitution. According to this type of medicine, the constitution is the specific way a person's organs affect health and how he or she looks, thinks, behaves, and responds to treatment. Also called Korean acupuncture.

contiguous
Touching or very close together.

contiguous lymphoma (kun-TIG-yoo-us lim-FOH-muh)
Lymphoma in which the lymph nodes containing cancer are next to each other.

continent reservoir (KAHN-tih-nent RES-er-vwar)
A pouch formed from a piece of small intestine to hold urine after the bladder has been removed.

contingency management
In medicine, a treatment plan that gives immediate rewards for desired changes in behavior. It is based on the principle that if a good behavior is rewarded, it is more likely to be repeated. This is often used in the treatment of drug and alcohol abuse, and is being studied as a smoking cessation method.

continuous hyperthermic peritoneal perfusion
CHPP. A procedure that bathes the abdominal cavity in fluid that contains anticancer drugs. This fluid is warmer than body temperature. This procedure appears to kill cancer cells without harming normal cells.

continuous infusion
The administration of a fluid into a blood vessel, usually over a prolonged period of time.


Contracted Health Services
This is the referral system that tribes, Indian Health Service and/or urban Indian clinics use to obtain services not available from their local community facility. contraindication
A symptom or medical condition that makes a particular treatment or procedure inadvisable because a person is likely to have a bad reaction. For example, having a bleeding disorder is a contraindication for taking aspirin because treatment with aspirin may cause excess bleeding.

contralateral
Having to do with the opposite side of the body.

contrast material
A dye or other substance that helps show abnormal areas inside the body. It is given by injection into a vein, by enema, or by mouth. Contrast material may be used with x-rays, CT scans, MRI, or other imaging tests.

control animal
An animal in a study that does not receive the treatment being tested. Comparing the health of control animals with the health of treated animals allows researchers to evaluate the effects of a treatment more accurately.

control group
In a clinical trial, the group that does not receive the new treatment being studied. This group is compared to the group that receives the new treatment, to see if the new treatment works.

controlled clinical trial
A clinical study that includes a comparison (control) group. The comparison group receives a placebo, another treatment, or no treatment at all.

controlled low-voltage electrical stimulation (kun-TROLD loh VOLE-tij ee-LEK-trih-kul STIM-yoo-LAY-shun)
A technique in which mild electric currents are applied to some areas of the skin by a small power pack connected to two electrodes. Also called TENS (transcutaneous electric nerve stimulation).

controlled study
An experiment or clinical trial that includes a comparison (control) group.

conventional medicine (kun-VEN-shuh-nul MED-ih-sin)
A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery. Also called Western medicine, mainstream medicine, orthodox medicine, biomedicine, and allopathic medicine.

conventional therapy (kun-VEN-shuh-nul THAYR-uh-pee)
A currently accepted and widely used treatment for a certain type of disease, based on the results of past research. Also called conventional treatment.

conventional treatment
A currently accepted and widely used treatment for a certain type of disease, based on the results of past research. Also called conventional therapy.

cope (kope)
To adjust to new situations and overcome problems.

coping skills (KOH-ping skilz)
The methods a person uses to deal with stressful situations. These may help a person face a situation, take action, and be flexible and persistent in solving problems.

CoQ10
A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called coenzyme Q10, Q10, vitamin Q10, and ubiquinone.

cordectomy (kor-DEK-tuh-mee)
An operation on the vocal cords or on the spinal cord.

cordycepin
An anticancer drug that belongs to a family of drugs called antitumor antibiotics.

core biopsy
The removal of a tissue sample with a needle for examination under a microscope.

cornea
The transparent part of the eye that covers the iris and the pupil and allows light to enter the inside.

coronary artery disease (KOR-uh-nayr-ee AR-tuh-ree dih-ZEEZ)
CAD. A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). Coronary artery disease is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of coronary artery disease is increased by having a family history of coronary artery disease before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary heart disease.

coronary heart disease (KOR-uh-nayr-ee hart dih-ZEEZ)
A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). Coronary heart disease is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of coronary heart disease is increased by having a family history of coronary heart disease before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary artery disease (CAD).

corpus
The body of the uterus.

corticosteroid (KOR-tih-koh-STAIR-oyd)
Any steroid hormone made in the adrenal cortex (the outer part of the adrenal gland). They are also made in the laboratory. Corticosteroids have many different effects in the body, and are used to treat many different conditions. They may be used as hormone replacement, to suppress the immune system, and to treat some side effects of cancer and its treatment. Corticosteroids are also used to treat certain lymphomas and lymphoid leukemias.

corticotropin (KOR-tih-koh-TROH-pin)
A form of the hormone adrenocorticotropic hormone (ACTH). It belongs to the family of drugs called corticosteroids.

cortisone
A natural steroid hormone produced in the adrenal gland. It can also be made in the laboratory. Cortisone reduces swelling and can suppress immune responses.

Corynebacterium granulosum
A bacterium that may stimulate the immune system to fight cancer.

coumestan
An estrogen-like substance (phytoestrogen) made by some plants. Coumestans may have anticancer effects.

coumestrol
A type of coumestan. Coumestans are estrogen-like substances (phytoestrogens) made by some plants. Coumestans may have anticancer effects.

counseling (KOWN-suh-ling)
The process by which a professional counselor helps a person cope with mental or emotional distress, and understand and solve personal problems.

COX inhibitor (kox in-HIH-bih-ter)
A type of drug that is used to treat inflammation and pain, and is being studied in the prevention and treatment of cancer. COX inhibitors belong to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Also called cyclooxygenase inhibitor.

COX-2 inhibitor
Cyclooxygenase-2 inhibitor. A nonsteroidal anti-inflammatory drug used to relieve pain and inflammation. COX-2 inhibitors are being studied in the prevention of colon polyps, and as anticancer drugs.

CP-358,774
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epidermal growth factor receptor tyrosine kinase inhibitors. Also called erlotinib.

CP-547,632
A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called vascular endothelial growth factor (VEGF) receptor inhibitors and angiogenesis inhibitors.

CP-609,754
A substance that is being studied in the treatment of cancer.

CP-724,714
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called ErbB receptor tyrosine kinase inhibitors.

CP4071
A substance that is being studied in the treatment of cancer.

CpG 7909
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called immune system stimulants.

CPT 11
An anticancer drug that belongs to a family of drugs called topoisomerase inhibitors. It is a camptothecin analogue. Also called irinotecan.

CQS
Chloroquinoxaline sulfonamide. A substance that is being studied in the treatment of cancer.

craniopharyngioma (KRAY-nee-o-fah-rin-jee-O-ma)
A benign brain tumor that may be considered malignant because it can damage the hypothalamus, the area of the brain that controls body temperature, hunger, and thirst.

craniotomy (kray-nee-AH-toe-mee)
An operation in which an opening is made in the skull.

creatine
A substance that is made by the body and used to store energy. It is being studied in the treatment of weight loss related to cancer. It is derived from the amino acid arginine.

creatinine (cree-AT-ih-nin)
A compound that is excreted from the body in urine. Creatinine levels are measured to monitor kidney function.

crib death
The sudden and unexpected death of a healthy child who is younger than one year old, usually during sleep. The cause of crib death is not known. Also called sudden infant death syndrome (SIDS).

cribriform
Pierced with small holes as in a sieve. Refers to the appearance of a tumor when viewed under a microscope. The tumor appears to have open spaces or small holes inside.

crisis intervention (KRY-sis IN-tur-VEN-shun)
Immediate, short-term counseling (talking with a professional counselor) to stop a critical emotional incident (e.g., attempted suicide or drug overdose) from getting worse. Crisis intervention is not meant to solve the problem that led up to the crisis.

crisnatol mesylate
An anticancer drug that interferes with the DNA in cancer cells.

Crocinic Acid
A liquid that has been promoted as a treatment for a wide range of diseases, including cancer. The ingredients thought to be in Crocinic Acid have been tested, and none of them has been shown to be effective in treating any form of cancer. Crocinic Acid is not available in the United States. Also called Entelev, Sheridan's Formula, Jim's Juice, Cancell, JS'114, JS'101, 126'F, and Cantron.

Crohn's disease (krone)
Chronic inflammation of the gastrointestinal tract, most commonly the small intestine and colon. Crohn's disease increases the risk for colorectal cancer and small intestine cancer. Also called regional enteritis.

cruciferous vegetable
A member of the family of vegetables that includes kale, collard greens, broccoli, cauliflower, cabbage, Brussels sprouts, and turnips. These vegetables contain substances that may protect against cancer.

cryopreservation
The process of cooling and storing cells, tissues, or organs at very low or freezing temperatures to save them for future use.

cryosurgery (KRY-o-SER-juh-ree)
A procedure performed with an instrument that freezes and destroys abnormal tissues.

cryotherapy
Any method that uses cold temperature to treat disease.

cryptorchidism (kript-OR-kid-izm)
A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum. Cryptorchidism may increase the risk for development of testicular cancer. Also called undescended testicles.

CSF
Cerebrospinal fluid. The fluid flowing around the brain and spinal cord. CSF is produced in the ventricles of the brain.

CT scan
Computed tomography scan. A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized tomography and computerized axial tomography (CAT) scan.

CT-2103
A protein that can be linked to a chemotherapy drug to deliver the drug directly to the tumor with fewer side effects. It is being studied in the treatment of cancer. Also called polyglutamate paclitaxel.

CT-2106
A form of the anticancer drug camptothecin that may have fewer side effects and work better than camptothecin. It is being studied in the treatment of cancer. It belongs to the family of drugs called DNA topoisomerase inhibitors. Also called polyglutamate camptothecin.

CT-2584
A substance that is being studied in the treatment of cancer. It may prevent the growth of blood vessels from surrounding tissue into a solid tumor.

CTC
Computed tomographic colonography. A procedure in which a detailed picture of the colon is created by an x-ray machine linked to a computer. Also called computed tomography (CT) scan or computerized axial tomography (CAT) scan of the colon.

cultured cell
A human, plant, or animal cell that has been adapted to grow in the laboratory.

cultured cell line
Cells of a single type (human, animal, or plant) that have been adapted to grow continuously in the laboratory and are used in research.

cumulative dose
In medicine, the total amount of a drug or radiation given to a patient over time; for example, the total dose of radiation given in a series of radiation treatments.

cupping (KUP-ping)
A procedure in which a rounded glass cup is warmed and placed upside down over an area of the body, creating suction that holds the cup to the skin. Cupping increases the flow of blood. In traditional Chinese medicine, it is also thought to increase the flow of qi (vital energy).

curcumin
A yellow pigment of the spice turmeric that is being studied in cancer prevention.

cure
To heal or restore health; a treatment to restore health.

curettage (kyoo-reh-TAHZH)
Removal of tissue with a curette (a spoon-shaped instrument with a sharp edge).

curette (kyoo-RET)
A spoon-shaped instrument with a sharp edge.

cutaneous (kyoo-TAY-nee-us)
Having to do with the skin.

cutaneous breast cancer
Cancer that has spread from the breast to the skin.

cutaneous T-cell lymphoma
A disease in which certain cells of the lymph system (called T lymphocytes) become cancerous (malignant) and affect the skin.

cyanogenic glucoside
A plant compound that contains sugar and produces cyanide.

cyanosis
Blue-colored skin caused by too little oxygen in the blood.

cyclooxygenase inhibitor
A type of drug that is used to treat inflammation and pain, and is being studied in the prevention and treatment of cancer. COX inhibitors belong to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Also called COX inhibitor.

cyclooxygenase-2 inhibitor
COX-2 inhibitor. A nonsteroidal anti-inflammatory drug used to relieve pain and inflammation. COX-2 inhibitors are being studied in the prevention of colon polyps, and as anticancer drugs.

cyclophosphamide
An anticancer drug that belongs to the family of drugs called alkylating agents.

cyclosporine
A drug used to help reduce the risk of rejection of organ and bone marrow transplants by the body. It is also used in clinical trials to make cancer cells more sensitive to anticancer drugs.

cyproheptadine (si-pro-HEP-ta-deen)
A drug that is used to treat asthma, allergies, and colds, and to relieve itching caused by certain skin disorders. It has also been used to stimulate appetite and weight gain, and is being studied in the treatment of weight loss caused by cancer and its treatment. Cyproheptadine belongs to the family of drugs called antihistamines.

cyproterone acetate
A synthetic hormone being studied for treatment of hot flashes in men with prostate cancer who have had both testicles removed by surgery.

cyst (sist)
A sac or capsule in the body. It may be filled with fluid or other material.

cystectomy (sis-TEK-tuh-mee)
Surgery to remove all or part of the bladder.

cystic fibrosis
A common hereditary disease in which exocrine (secretory) glands produce abnormally thick mucus. This mucus can cause problems in digestion, breathing, and body cooling.

cystoprostatectomy (SIS-toh-pros-tuh-TEK-toh-mee)
Surgery to remove the bladder (the organ that holds urine), the seminal vesicles, and the prostate. The seminal vesicles and prostate are glands in the male reproductive system that help make semen. Also called prostatocystectomy.

cystosarcoma phyllodes
CSP. A type of tumor found in breast tissue. It is often large and bulky and grows quickly. It is usually benign (not cancer), but may be malignant (cancer). Also called phyllodes tumor.

cystoscope (SISS-toh-SKOPE)
A thin, tube-like instrument used to look inside the bladder and urethra. A cystoscope has a light and a lens for viewing and may have a tool to remove tissue.

cystoscopy (siss-TOSS-koh-pee)
Examination of the bladder and urethra using a cystoscope, inserted into the urethra. A cystoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.

cystourethrectomy (SIS-toh-yoor-eh-THREK-toh-mee)
Surgery to remove the bladder (the organ that holds urine) and urethra (the tube through which urine leaves the body).

cytarabine
An anticancer drug that belongs to the family of drugs called antimetabolites.

cytochlor
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called radiosensitizers.

cytochrome P450 enzyme system
A group of enzymes involved in drug metabolism and found in high levels in the liver. These enzymes change many drugs, including anticancer drugs, into less toxic forms that are easier for the body to excrete.

cytogenetics (SITE-o-juh-NET-iks)
The study of chromosomes and chromosomal abnormalities.

cytokine
A substance that is produced by cells of the immune system and can affect the immune response. Cytokines can also be produced in the laboratory by recombinant DNA technology and given to people to affect immune responses.

cytology
The study of cells using a microscope.

cytomegalovirus
CMV. A virus that may be carried in an inactive state for life by healthy individuals. It is a cause of severe pneumonia in people with a suppressed immune system, such as those undergoing bone marrow transplantation or those with leukemia or lymphoma.

cytopenia
A reduction in the number of blood cells.

cytoplasm
The fluid inside a cell but outside the cell's nucleus. Most chemical reactions in a cell take place in the cytoplasm.

cytotoxic
Cell-killing.

cytotoxic chemotherapy (SY-toh-TOK-sik kee-moh-THAYR-uh-pee)
Anticancer drugs that kill cells, especially cancer cells.

cytotoxic T cell
A type of white blood cell that can directly destroy specific cells. T cells can be separated from other blood cells, grown in the laboratory, and then given to a patient to destroy tumor cells. Certain cytokines can also be given to a patient to help form cytotoxic T cells in the patient's body.

ABCDEFGHIJKLMNOPQRSTUVWXYZ


D&C
Dilation and curettage. A minor operation in which the cervix is expanded enough (dilation) to permit the cervical canal and uterine lining to be scraped with a spoon-shaped instrument called a curette (curettage). Also called dilatation and curettage.

D-20761
A synthetic luteinizing hormone-releasing hormone (LH-RH) antagonist that suppresses LH and sex steroid levels.

da-huang
Rheum palmatum or Rheum officinale. The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Also called rhubarb, Chinese rhubarb, Indian rhubarb, and Turkish rhubarb.

DACA
Acridine carboxamide. A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called topoisomerase inhibitors.

dacarbazine
An anticancer drug that belongs to the family of drugs called alkylating agents.

dacliximab
A monoclonal antibody that is being studied in the treatment of adult T-cell leukemia and in the treatment of cytopenia (low blood cell count). Also called daclizumab.

daclizumab
A monoclonal antibody that is being studied in the treatment of adult T-cell leukemia and in the treatment of cytopenia (low blood cell count). Also called dacliximab.

dactinomycin
An anticancer drug that belongs to the family of drugs called antitumor antibiotics.

daidzein
An isoflavone found in soy products. Soy isoflavones are being studied in the prevention of cancer.

dalteparin
A drug that helps prevent the formation of blood clots; it belongs to the family of drugs called anticoagulants.

danazol
A synthetic hormone that belongs to the family of drugs called androgens and is used to treat endometriosis. It is being evaluated in the treatment of endometrial cancer.

darbepoetin alfa (dar-be-POE-e-tin AL-fa)
A substance made in the laboratory that stimulates the bone marrow to produce red blood cells. It belongs to the family of drugs called antianemics.

dark-field microscope
A microscope (device used to magnify small objects) in which objects are lit at a very low angle from the side so that the background appears dark and the objects show up against this dark background.

Data Safety and Monitoring Committee
An impartial group that oversees a clinical trial and reviews the results to see if they are acceptable. This group determines if the trial should be changed or closed.

daunorubicin
An anticancer drug that belongs to the family of drugs called antitumor antibiotics. It is an anthracycline.

DCIS
Ductal carcinoma in situ. A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called intraductal carcinoma.

DDS
Denys-Drash syndrome. A rare disorder that causes kidney failure before age 3, abnormal development of the sexual organs, and, in most cases, Wilms' tumor (a type of kidney cancer). Children with Denys-Drash syndrome are also at high risk of some other types of cancer.

de novo (dih NO-vo)
In cancer, the first occurrence of cancer in the body.

de qi sensation (duh-CHEE sen-SAY-shun)
Tingling, numbness, heaviness, and other feelings that occur after an acupuncture needle has been properly placed in the body. The needle may be twirled, moved up and down at different speeds and depths, heated, or charged with a small electric current until the de qi sensation occurs.

death cap
Amanita phalloides. A type of poisonous mushroom that has harmful effects on the kidneys and liver. It is responsible for most fatal cases of mushroom poisoning.

decitabine
An anticancer drug that belongs to the family of drugs called antimetabolites.

decortication (de-KOR-tih-KAY-shun)
Removal of part or all of the external surface of an organ.

deferoxamine
An iron-chelating agent that removes iron from tumors by inhibiting DNA synthesis and causing cancer cell death. It is used in conjunction with other anticancer agents in pediatric neuroblastoma therapy.

defibrotide
A substance that is being studied in the prevention of veno-occlusive disease, a rare complication of high-dose chemotherapy and stem cell transplantation in which small veins in the liver become blocked.

deficiency
In medicine, a shortage of a substance (such as a vitamin or mineral) needed by the body.

degenerative disease
A disease in which the function or structure of the affected tissues or organs changes for the worse over time. Osteoarthritis, osteoporosis, and Alzheimer's disease are examples.

dehydration
A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration.

dehydroepiandrosterone
DHEA. A substance that is being studied in the prevention of cancer. It belongs to the family of drugs called steroids.

delayed-type hypersensitivity response
DTH. An inflammatory response that develops 24 to 72 hours after exposure to an antigen that the immune system recognizes as foreign. This type of immune response involves mainly T cells rather than antibodies (which are made by B cells).

delirium (deh-LEER-ee-um)
A mental state in which a person is confused, disoriented, and not able to think or remember clearly. The person may also be agitated and have hallucinations, and extreme excitement.

dementia (dih-MEN-shuh)
A condition in which a person loses the ability to think, remember, learn, make decisions, and solve problems. Symptoms may also include personality changes and emotional problems. There are many causes of dementia, including Alzheimer's disease, brain cancer, and brain injury. Dementia usually gets worse over time.

dendritic cell
A special type of antigen-presenting cell (APC) that activates T lymphocytes.

dendritic cell vaccine
A vaccine made of antigens and dendritic antigen-presenting cells (APCs).

denial (deh-NY-ul)
In psychiatry, a state in which a person is unable or unwilling to see the truth or reality about an issue or situation.

denileukin diftitox (DEN-i-loo-kin DIF-ti-toks)
A substance used to treat cutaneous T-cell lymphoma when other treatments have not worked. It is also being studied in the treatment of chronic lymphocytic leukemia that has not responded to treatment. It belongs to the family of drugs called biological therapy agents.

dental implant
A metal, root-shaped device that is placed surgically in the jawbone. It acts as an anchor for attaching false teeth (crowns or bridges).

dentist
A health professional who specializes in caring for the teeth, gums, and other tissues in the mouth.

Denys-Drash syndrome
DDS. A rare disorder that causes kidney failure before age 3, abnormal development of the sexual organs, and, in most cases, Wilms' tumor (a type of kidney cancer). Children with Denys-Drash syndrome are also at high risk of some other types of cancer.

deoxycytidine
A drug that protects healthy tissues from the toxic effects of anticancer drugs.

deoxyribonucleic acid
DNA. The molecules inside cells that carry genetic information and pass it from one generation to the next.

DepoFoam-encapsulated cytarabine
The anticancer drug cytarabine formulated inside small particles of a synthetic lipid material called DepoFoam. This dosage form slowly releases the drug and provides a sustained action.

depression (dee-PREH-shun)
A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.

depsipeptide
A substance that is made naturally by some bacteria, fungi, and other organisms, and can also be made in the laboratory. Depsipeptides are being studied in the treatment of cancer.

derivative
In chemistry, a compound produced from or related to another.

dermatitis
Inflammation of the skin.

dermatofibrosarcoma protuberans (DER-ma-toe-FI-bro-sar-KO-ma pro-TOO-ber-anz)
A type of tumor that begins as a hard nodule and grows slowly. These tumors are usually found in the dermis (the inner layer of the two main layers of tissue that make up the skin) of the limbs or trunk of the body. They can grow into surrounding tissue but do not spread to other parts of the body. These tumors are related to giant cell fibroblastoma.

dermatologist (der-ma-TAH-loh-jist)
A doctor who has special training to diagnose and treat skin problems.

dermis (DER-mis)
The lower or inner layer of the two main layers of tissue that make up the skin.

dermoid cyst (DER-moyd sist)
A type of benign (noncancerous) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that often contains several different types of tissue such as hair, muscle, and bone. Also called a mature teratoma.

DES
Diethylstilbestrol (dye-ETH-ul-stil-BES-trol). A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. DES may increase the risk of uterine, ovarian, or breast cancer in women who took it. DES also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to DES before birth.

deslorelin
A substance that is being studied in the treatment of cancer as a way to block sex hormones made by the ovaries or testicles. It belongs to the family of drugs called gonadotropin-releasing hormone analogs.

desmoid tumor
A tumor of the tissue that surrounds muscles, usually in the abdomen. A desmoid tumor rarely metastasizes (spreads to other parts of the body). Also called aggressive fibromatosis, especially when the tumor is outside the abdomen.

desmoplastic
Causing or forming adhesions or fibrous connective tissue within a tumor.

desmoplastic melanoma
A rare form of malignant melanoma marked by nonpigmented lesions on sun-exposed areas of the body, most commonly on the head and neck.

desmoplastic small round cell tumor (dez-mo-PLAS-tik...)
A rare, aggressive cancer that usually affects young males and usually is located in the abdomen.

detoxify (dee-TOX-ih-fy)
To make something less poisonous or harmful. It may refer to the process of removing toxins, poisons, or other harmful substances from the body.

developmental stage (dee-VEH-lup-MEN-tul)
The physical, mental, and emotional stages a child goes through as they grow and mature.

dexamethasone
A synthetic steroid (similar to steroid hormones produced naturally in the adrenal gland). Dexamethasone is used to treat leukemia and lymphoma and may be used to treat some of the problems caused by other cancers and their treatment.

dexmethylphenidate
A substance that is being studied in the treatment of fatigue and nervous system side effects caused by chemotherapy. It belongs to the family of drugs called central nervous system stimulants.

dexrazoxane
A drug used to protect the heart from the toxic effects of anthracycline drugs such as doxorubicin. It belongs to the family of drugs called chemoprotective agents.

dextroamphetamine-amphetamine
A combination of drugs that is used as a treatment for attention deficit hyperactivity disorder (ADHD) and narcolepsy (a sleep disorder). It belongs to the family of drugs called stimulants. Also called Adderall.

dextromethorphan acetic acid
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

DFMO
Difluoromethylornithine. A substance that is being studied in the treatment of cancer.

DHA-paclitaxel
A combination of DHA (a natural fatty acid) and paclitaxel (an anticancer drug) that is being studied in the treatment of cancer.

DHEA
Dehydroepiandrosterone. A substance that is being studied in the prevention of cancer. It belongs to the family of drugs called steroids.

di-dgA-RFB4
An anticancer drug that is a combination of a monoclonal antibody (RFB4) and an immunotoxin (dgA).

diabetes (dye-a-BEE-teez)
A disease in which the body does not properly control the amount of sugar in the blood. As a result, the level of sugar in the blood is too high. This disease occurs when the body does not produce enough insulin or does not use it properly.

diabetes mellitus (dye-a-BEE-teez MEL-ih-tus)
A group of disorders in which there is a defect in the transfer of glucose (sugar) from the bloodstream into cells, leading to abnormally high levels of blood sugar (hyperglycemia).

diagnosis
The process of identifying a disease by the signs and symptoms.

diagnostic mammogram
X-ray of the breasts used to check for breast cancer after a lump or other sign or symptom of breast cancer has been found.

diagnostic procedure
A method used to identify a disease.

diagnostic trial
A research study that evaluates methods of detecting disease.

dialysis (dye-AL-ih-sis)
The process of filtering the blood when the kidneys are not able to cleanse it.

diameter
The length of a straight line that extends from one edge of a tumor or other object, through its center and to the opposite edge. It is usually used to measure the size of round or spherical shapes.

diaphragm (DY-a-fram)
The thin muscle below the lungs and heart that separates the chest from the abdomen.

diarrhea
Frequent and watery bowel movements.

diathermy (DYE-a-ther-mee)
The use of heat to destroy abnormal cells. Also called cauterization or electrodiathermy.

diaziquone
AZQ. An anticancer drug that is able to cross the blood-brain barrier and kill cancer cells in the central nervous system.

didanosine
A drug used in the treatment of infections caused by viruses.

DIEP flap
A type of breast reconstruction in which blood vessels called deep inferior epigastric perforators (DIEP), and the skin and fat connected to them are removed from the lower abdomen and used for reconstruction. Muscle is left in place.

diet
The things a person eats and drinks.

dietary protocol (DY-uh-TAYR-ee PROH-tuh-KOL)
A detailed diet plan that states what, how, and when a person will eat and drink. It may be used to test how a specific diet affects a health outcome, such as lower cholesterol.

dietary supplement (DY-uh-TAYR-ee SUH-pleh-ment)
A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredients (including vitamins, minerals, herbs, amino acids, and enzymes). Also called nutritional supplement.

diethylstilbestrol (dye-EH-thul-stil-BES-trol)
DES. A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. DES may increase the risk of uterine, ovarian, or breast cancer in women who took it. DES also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to DES before birth.

dietitian (dy-eh-TIH-shun)
A health professional with special training in nutrition who can help with dietary choices. Also called a nutritionist.

differentiation
In cancer, refers to how mature (developed) the cancer cells are in a tumor. Differentiated tumor cells resemble normal cells and tend to grow and spread at a slower rate than undifferentiated or poorly differentiated tumor cells, which lack the structure and function of normal cells and grow uncontrollably.

diffuse
Widely spread; not localized or confined.

diffuse large B-cell lymphoma (lim-FOH-muh)
A type of B-cell non-Hodgkin's lymphoma (cancer of the immune system) that is usually aggressive (fast-growing). It is the most common type of non-Hodgkin's lymphoma, and is marked by rapidly growing tumors in the lymph nodes, spleen, liver, bone marrow, or other organs. Other symptoms include fever, night sweats, and weight loss. There are several subtypes of diffuse large B-cell lymphoma.

difluoromethylornithine
DFMO. A substance that is being studied in the treatment of cancer.

digestion (dy-JES-chun)
The process of breaking down food into substances the body can use for energy, tissue growth, and repair.

digestive system (dye-JES-tiv)
The organs that take in food and turn it into products that the body can use to stay healthy. Waste products the body cannot use leave the body through bowel movements. The digestive system includes the salivary glands, mouth, esophagus, stomach, liver, pancreas, gallbladder, small and large intestines, and rectum.

digestive tract (dy-JES-tiv)
The organs through which food and liquids pass when they are swallowed, digested, and eliminated. These organs are the mouth, esophagus, stomach, small and large intestines, and rectum and anus.

digital mammography
A technique that uses a computer, rather than x-ray film, to record x-ray images of the breast.

digital photography
A type of photography in which images can be viewed on a computer screen.

digital rectal examination (DIH-jih-tul REK-tul eg-zam-ih-NAY-shun)
DRE. An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities.

dihematoporphyrin ether
Used in photodynamic therapy, a drug that is absorbed by tumor cells; when exposed to light, it becomes active and kills the cancer cells.

dilatation and curettage (DIH-luh-TA-shun and KYUR-eh-TAHJ)
D&C. A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called dilation and curettage.

dilate (DYE-late)
To widen or enlarge an opening or hollow structure beyond its usual size, such as the pupil of the eye or a blood vessel.

dilation and curettage (DY-LAY-shun and KYUR-eh-TAHJ)
D&C. A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called dilatation and curettage.

dilator (DYE-lay-tor)
A device used to stretch or enlarge an opening.

dilute (dy-LOOT)
To make something thinner, weaker, less concentrated, or less pure by adding something to it.

dimesna
A drug that belongs to the family of drugs called chemoprotective agents.

dimethyl sulfoxide
A colorless liquid that readily dissolves many chemicals and penetrates animal and plant tissues. It is used in human medicine, veterinary medicine, and pharmaceuticals.

dimethylxanthenone acetic acid
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

diphenhydramine (dy-fen-HY-druh-meen)
A drug used to treat allergies and relieve cough and itching caused by insect bites, sunburn, and poison oak or ivy. It is also used to treat mild Parkinson's disease, to prevent and treat motion sickness, to relieve cough and cold symptoms, and as a sleep aid. It belongs to the family of drugs called antihistamines.

diphosphonate
A drug used to treat osteoporosis and the bone pain caused by some types of cancer. Also called bisphosphonate.

dipyridamole
A drug that prevents blood cell clumping and enhances the effectiveness of fluorouracil and other chemotherapeutic agents.

discharge (DIS-charj)
In medicine, a fluid that comes out of the body. Discharge can be normal or a sign of disease. Discharge also means release of a patient from care.

disease progression
Cancer that continues to grow or spread.

disease-free survival
Length of time after treatment during which no cancer is found. Can be reported for an individual patient or for a study population.

disease-specific survival
The percentage of subjects in a study who have survived a particular disease for a defined period of time. Usually reported as time since diagnosis or treatment. In calculating this percentage, only deaths from the disease being studied are counted. Subjects who died from some other cause are not included in the calculation.

disorder (diss-ORE-der)
In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

disseminate (dih-SEM-ih-NATE)
Scatter or distribute over a large area or range.

distal
In medicine, refers to a part of the body that is farther away from the center of the body than another part. For example, the fingers are distal to the shoulder. The opposite is proximal.

distal pancreatectomy
Removal of the body and tail of the pancreas.

distant cancer
Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes. Also known as distant metastasis.

distant metastasis
Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes. Also known as distant cancer.

distraction
In medicine, a pain relief method that takes the patient's attention away from the pain.

distress (dih-STRESS)
Extreme mental or physical pain or suffering.

disulfiram
A drug that slows the metabolism of retinoids, allowing them to act over a longer period of time.

diuretic
A drug that increases the production of urine.

diverticulosis
A condition marked by small sacs or pouches (diverticula) in the walls of an organ such as the stomach or colon. These sacs can become inflamed and cause a condition called diverticulitis, which may be a risk factor for certain types of cancer.

DJ-927
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxane derivatives.

DNA
Deoxyribonucleic acid. The molecules inside cells that carry genetic information and pass it from one generation to the next.

DNR order
Do not resuscitate order. A type of advance directive in which a person states that healthcare providers should not perform cardiopulmonary resuscitation (restarting the heart) if his or her heart or breathing stops.

do not resuscitate order (ree-SUH-sih-TAYT)
DNR order. A type of advance directive in which a person states that healthcare providers should not perform cardiopulmonary resuscitation (restarting the heart) if his or her heart or breathing stops.

docetaxel
An anticancer drug that belongs to the family of drugs called mitotic inhibitors.

dock
Rumex acetosella. A plant that has been used in some cultures to treat certain medical problems. It may have anticancer effects. Also called sheep sorrel and sorrel.

dolasetron
A drug that prevents or reduces nausea and vomiting. It belongs to the family of drugs called antiemetics.

dolastatin 10
An anticancer drug that belongs to the family of drugs called mitotic inhibitors.

donepezil
A drug used in the treatment of Alzheimer's disease. It belongs to the family of drugs called cholinesterase inhibitors. It is being studied in the treatment of side effects caused by radiation therapy to the brain.

dong quai (dahng-kwye)
Angelica sinensis. An herb native to China. A substance taken from the roots has been used in traditional Chinese medicine to treat menstrual and menopausal problems. Dong quai may increase the effect of the drug warfarin (a blood-thinner).

dose
The amount of medicine taken, or radiation given, at one time.

dose-dense chemotherapy
A chemotherapy treatment plan in which drugs are given with less time between treatments than in a standard chemotherapy treatment plan.

dose-dependent
Refers to the effects of treatment with a drug. If the effects change when the dose of the drug is changed, the effects are said to be dose-dependent.

dose-limiting
Describes side effects of a drug or other treatment that are serious enough to prevent an increase in dose or level of that treatment.

dose-rate
The strength of a treatment given over a period of time.

dosimetrist (do-SIM-uh-trist)
A person who determines the proper radiation dose for treatment.

dosimetry (doh-SIH-muh-tree)
Measurement of radiation exposure from x-rays, gamma rays, or other types of radiation used in the treatment or detection of diseases, including cancer.

double-blinded
A clinical trial in which neither the medical staff nor the person knows which of several possible therapies the person is receiving.

double-contrast barium enema
A procedure in which x-rays of the colon and rectum are taken after a liquid containing barium is put into the rectum. Barium is a silver-white metallic compound that outlines the colon and rectum on an x-ray and helps show abnormalities. Air is put into the rectum and colon to further enhance the x-ray.

doubling time (DUH-bling...)
In biology, the amount of time it takes for one cell to divide or for a group of cells (such as a tumor) to double in size. The doubling time is different for different kinds of cancer cells or tumors.

douche (DOOSH)
A procedure in which water or a medicated solution is used to clean the vagina and cervix.

Down syndrome
A disorder caused by the presence of an extra chromosome 21 and characterized by mental retardation and distinguishing physical features.

doxercalciferol
A substance that is being studied in the prevention of recurrent prostate cancer. It belongs to the family of drugs called vitamin D analogs.

doxorubicin
An anticancer drug that belongs to the family of drugs called antitumor antibiotics. It is an anthracycline. Also called Adriamycin.

doxycycline
An antibiotic drug used to treat infection.

DPA
Durable power of attorney. A document that gives a person (such as a relative, lawyer, or friend) the authority to make legal or financial decisions for another person. It may become active immediately, or when that person loses the ability to make decisions for himself or herself, depending on how it is written.

DPPE
Belongs to a group of antihormone drugs.

drain
In medicine, to remove fluid as it collects; or, a tube or wick-like device used to remove fluid from a body cavity, wound, or infected area.

DRE
Digital rectal examination. An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities.

dronabinol
A synthetic pill form of delta-9-tetrahydrocannabinol (THC), an active ingredient in marijuana that is used to treat nausea and vomiting associated with cancer chemotherapy.

droperidol (droh-PAYR-ih-dol)
A drug that is used to prevent nausea and vomiting in patients who receive anesthesia before surgery. It is also used to treat anxiety. Droperidol belongs to the families of drugs called antiemetics, adjunct anesthesia, and antipsychotics.

drug
Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

drug abuse (...uh-BYOOS)
The use of illegal drugs or the use of prescription or over-the-counter drugs for purposes other than those for which they are meant to be used, or in large amounts. Drug abuse may lead to social, physical, emotional, and job-related problems.

drug interaction ( IN-ter-AK-shun)
A change in the way a drug acts in the body when taken with certain other drugs, herbals, or foods, or when taken with certain medical conditions. Drug interactions may cause the drug to be more or less effective, or cause effects on the body that are not expected.

drug resistance
The failure of cancer cells, viruses, or bacteria to respond to a drug used to kill or weaken them. The cells, viruses, or bacteria may be resistant to the drug at the beginning of treatment, or may become resistant after being exposed to the drug.

drug tolerance
A condition that occurs when the body gets used to a medicine so that either more medicine is needed or different medicine is needed.

dry orgasm
Sexual climax without the release of semen from the penis.

DTGM fusion protein
An anticancer drug formed by the combination of diphtheria toxin and a colony-stimulating factor (GM-CSF). The colony-stimulating factor is attracted to cancer cells, and the diphtheria toxin kills the cells.

DU 145
A cell line made from human prostate cancer cells that is used in the laboratory to study the way prostate cancer cells grow.

duct (dukt)
In medicine, a tube or vessel of the body through which fluids pass.

ductal carcinoma
The most common type of breast cancer. It begins in the cells that line the milk ducts in the breast.

ductal carcinoma in situ (DUK-tal KAR-sih-NOH-muh in SYE-too)
DCIS. A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, ductal carcinoma in situ may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called intraductal carcinoma.

ductal lavage (DUK-tal luh-VAHZ)
A method used to collect cells from milk ducts in the breast. A hair-size catheter (tube) is inserted into the nipple, and a small amount of salt water is released into the duct. The water picks up breast cells, and is removed. The cells are checked under a microscope. Ductal lavage may be used in addition to clinical breast examination and mammography to detect breast cancer.

Dukes' classification
A staging system used to describe the extent of colorectal cancer. Stages range from A (early stage) to D (advanced stage).

dumping syndrome
A condition that occurs when food or liquid moves too fast into the small intestine. Symptoms include cramps, nausea, diarrhea, sweating, weakness, and dizziness. Dumping syndrome sometimes occurs in people who have had part or all of their stomach removed.

duodenitis
Inflammation of the duodenum (the first part of the small intestine that connects to the stomach).

duodenum (doo-ah-DEE-num)
The first part of the small intestine that connects to the stomach.

durable power of attorney (DUR-uh-buluh-TUR-nee)
DPA. A document that gives a person (such as a relative, lawyer, or friend) the authority to make legal or financial decisions for another person. It may become active immediately, or when that person loses the ability to make decisions for himself or herself, depending on how it is written.

DX-52-1
An anticancer drug that belongs to the family of drugs called antitumor antibiotics. It is an anthracycline.

DX-8951f
An anticancer drug that belongs to the family of drugs called topoisomerase inhibitors. Also called exatecan mesylate.

dyscrasia
Disease. Usually refers to diseases of the blood.

dysesthesia
A condition in which a sense, especially touch, is distorted. Dysesthesia can cause an ordinary stimulus to be unpleasant or painful. It can also cause insensitivity to a stimulus.

dysfunction
A state of not functioning normally.

dysgeusia
A bad taste in the mouth. Also called parageusia.

dyspepsia
Upset stomach.

dysphagia
Difficulty swallowing.

dysphonia (diss-FOH-nee-uh)
Trouble with the voice when trying to talk, including hoarseness and change in pitch or quality or voice.

dysplasia (dis-PLAY-zha)
Cells that look abnormal under a microscope but are not cancer.

dysplastic nevi (dis-PLAS-tik NEE-vye)
Atypical moles; moles whose appearance is different from that of common moles. Dysplastic nevi are generally larger than ordinary moles and have irregular and indistinct borders. Their color frequently is not uniform and ranges from pink to dark brown; they usually are flat, but parts may be raised above the skin surface.

dysplastic nevus (dis-PLAS-tik NEE-vus)
An atypical mole; a mole whose appearance is different from that of a common mole. A dysplastic nevus is generally larger than an ordinary mole and has irregular and indistinct borders. Its color frequently is not uniform and ranges from pink to dark brown; it is usually flat, but parts may be raised above the skin surface.

dyspnea
Difficult, painful breathing or shortness of breath.

ABCDEFGHIJKLMNOPQRSTUVWXYZ


E7070
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called sulfonamides.

E7389
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitubulin agents.

early menopause (...MEN-uh-pawz)
A condition in which the ovaries stop working before age 40. Symptoms include hot flashes, mood swings, night sweats, vaginal dryness, and infertility. Some cancer treatments, such as chemotherapy, radiation therapy, and surgery can cause early menopause. Early menopause caused by cancer treatment may be temporary or permanent and may be treated with hormone replacement therapy. Also called premature ovarian failure or primary ovarian insufficiency.

early-stage breast cancer (ER-lee stayj brest KAN-ser)
Breast cancer that has not spread beyond the breast or the axillary lymph nodes. This includes ductal carcinoma in situ and stage I, stage IIA, stage IIB, and stage IIIA breast cancers.

Eastern red cedar (...SEE-der)
A type of evergreen tree with hard fragrant wood that is a member of the cypress family. The oil from the wood is used in soaps, shampoos, bath salts, perfumes, aromatherapy, and to keep insects away. It is also called cedarwood and red cedar. The scientific name is Juniperus virginiana.

EBV
Epstein-Barr virus. A common virus that remains dormant in most people. It has been associated with certain cancers, including Burkitt's lymphoma, immunoblastic lymphoma, and nasopharyngeal carcinoma.

ecchymosis
A small bruise caused by blood leaking from broken blood vessels into the tissues of the skin or mucous membranes.

eccrine gland
A type of simple sweat gland that is found in almost all regions of the skin. These glands produce sweat that reaches the surface of the skin by way of coiled ducts (tubes). The body is cooled as sweat evaporates from the skin.

echinacea (EH-kih-NAY-shuh)
An herb native to North America that has been used to prevent and treat the common cold and other respiratory infections. Echinacea may interfere with treatment that uses the immune system to fight cancer. Also called purple coneflower. Echinacea purpurea and Echinacea angustifolia.

echocardiography
A procedure that uses ultrasonic waves directed over the chest wall to obtain a graphic record of the heart's position, motion of the walls, or internal parts such as the valves.

ECT
Electroconvulsive therapy. A treatment for severe depression and certain mental disorders. A brief seizure is induced by giving electrical stimulation to the brain through electrodes placed on the scalp. Also called electroshock therapy.

ecteinascidin 743
An anticancer drug that inhibits the growth of cancer cells by disrupting the structure of tumor-cell DNA.

ectocervical
Having to do with the part of the cervix that protrudes into the vagina and is lined with epithelial cells.

eculizumab
A monoclonal antibody that is being studied in the prevention of red blood cell destruction in patients with paroxysmal nocturnal hemoglobinuria (a red blood cell disorder).

eczema (EK-zeh-muh)
A group of conditions in which the skin becomes inflamed, forms blisters, and becomes crusty, thick, and scaly. Eczema causes burning and itching, and may occur over a long period of time. Atopic dermatitis is the most common type of eczema.

edatrexate
An anticancer drug that belongs to a family of drugs called antimetabolites.

edema (eh-DEE-ma)
Swelling caused by excess fluid in body tissues.

edotecarin
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called topoisomerase I inhibitors. Also called J-107088.

edrecolomab
A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

EEG
Electroencephalogram. A recording of electrical activity in the brain. It is made by placing electrodes on the scalp (the skin covering the top of the head), and impulses are sent to a special machine. An EEG may be used to diagnose brain and sleep disorders.

EF5
A drug that is used to plan cancer treatment by measuring oxygen levels in tumor cells.

efaproxiral
A drug that may increase the effectiveness of radiation therapy. Also called RSR13.

effector cell
A cell that performs a specific function in response to a stimulus; usually used to describe cells in the immune system.

efficacy
Effectiveness. In medicine, the ability of an intervention (for example, a drug or surgery) to produce the desired beneficial effect.

effusion (eh-FYOO-zhun)
An abnormal collection of fluid in hollow spaces or between tissues of the body. For example, a pleural effusion is a collection of fluid between the two layers of membrane covering the lungs.

eflornithine
A substance that is being studied in the prevention of cancer. It belongs to the family of drugs called antiprotozoals.

EGb761
A substance that is being studied in the prevention of cognitive dysfunction (slowed ability to think, reason, concentrate, or remember) in patients receiving chemotherapy. It comes from ginkgo biloba leaves.

EGFR
Epidermal growth factor receptor. The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide. It is found at abnormally high levels on the surface of many types of cancer cells, so these cells may divide excessively in the presence of epidermal growth factor. Also known as ErbB1 or HER1.

ejaculation (i-JAK-yoo-LAY-shun)
The release of semen through the penis during orgasm.

EKB-569
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epidermal growth factor receptor inhibitors.

electroacupuncture (ee-LEK-troh-AK-yoo-punk-cher)
A procedure in which pulses of weak electrical current are sent through acupuncture needles into acupuncture points in the skin. This procedure is being studied in the prevention of nausea and vomiting in patients undergoing chemotherapy.

electroconvulsive therapy (ee-LEK-troh-kun-VUL-siv THAYR-uh-pee)
ETC. A treatment for severe depression and certain mental disorders. A brief seizure is induced by giving electrical stimulation to the brain through electrodes placed on the scalp. Also called electroshock therapy.

electrodermal response (ee-LEK-troh-DER-mul ...)
A change in the way electricity moves through the skin, often caused by stress or anxiety.

electrodesiccation (ee-LEK-troh-deh-sih-KAY-shun)
The drying of tissue by a high-frequency electric current applied with a needle-shaped electrode.

electroencephalogram (ee-LEK-troh-en-SEH-fuh-loh-gram)
EEG. A recording of electrical activity in the brain. It is made by placing electrodes on the scalp (the skin covering the top of the head), and impulses are sent to a special machine. An EEG may be used to diagnose brain and sleep disorders.

electrofulguration (ee-LEK-troh-ful-guh-RAY-shun)
A procedure to destroy tissue (such as a tumor) using an electric current. Also called fulguration.

electrolarynx (ee-LEK-troh-LAYR-inx)
A battery-operated device that makes a humming sound. It is used to help a person talk after removal of the larynx (voice box).

electrolyte (ee-LEK-troh-lite)
A substance that breaks up into ions (electrically charged particles) when it is dissolved in body fluids or water. Some examples of electrolytes are sodium, potassium, chloride, and calcium. Electrolytes are primarily responsible for the movement of nutrients into cells and the movement of wastes out of cells.

electromagnetic field (ee-LEK-troh-mag-NEH-tik feeld)
Low-energy radiation that comes from the interaction of electric and magnetic fields. Sources include power lines, electric appliances, radio waves, microwaves, and others. Also called electromagnetic radiation.

electromagnetic radiation (ee-LEK-troh-mag-NEH-tik ray-dee-AY-shun)
Low-energy radiation that comes from the interaction of electric and magnetic fields. Sources include power lines, electric appliances, radio waves, microwaves, and others. Also called electromagnetic field.

electron beam (ee-LEK-tron beem)
A stream of electrons (small negatively charged particles found in atoms) that can be used for radiation therapy.

electron microscope (ee-LEK-tron MY-kroh-SKOPE)
A microscope (device used to magnify small objects) that uses electrons (instead of light) to produce an enlarged image. An electron microscope shows tiny details better than any other type of microscope.

electroporation therapy (ee-LEK-troh-por-AY-shun THAYR-uh-pee)
EPT. Treatment that generates electrical pulses through an electrode placed in a tumor to enhance the ability of anticancer drugs to enter tumor cells.

electroshock therapy (ee-LEK-troh-shok THAYR-uh-pee)
A treatment for severe depression and certain mental disorders. A brief seizure is induced by giving electrical stimulation to the brain through electrodes placed on the scalp. Also called electroconvulsive therapy.

eligibility criteria
In clinical trials, requirements that must be met for an individual to be included in a study. These requirements help make sure that patients in a trial are similar to each other in terms of specific factors such as age, type and stage of cancer, general health, and previous treatment. When all participants meet the same eligibility criteria, it gives researchers greater confidence that results of the study are caused by the intervention being tested and not by other factors.

Eloxatin
A drug that is used to treat colorectal cancer and is being studied in the treatment of other types of cancer. It belongs to the family of drugs called platinum compounds. Also called oxaliplatin.

embolism (EM-bul-izm)
A block in an artery caused by blood clots or other substances, such as fat globules, infected tissue, or cancer cells.

embolization (EM-bo-lih-ZAY-shun)
The blocking of an artery by a clot or foreign material. Embolization can be done as treatment to block the flow of blood to a tumor.

embryo
Early stage in the development of a plant or an animal. In vertebrate animals (have a backbone or spinal column), this stage lasts from shortly after fertilization until all major body parts appear. In particular, in humans, this stage lasts from about 2 weeks after fertilization until the end of the seventh or eighth week of pregnancy.

embryoma
A mass of rapidly growing cells that begins in embryonic (fetal) tissue. Embryomas may be benign or malignant, and include neuroblastomas and Wilms' tumors. Also called embryonal tumor.

embryonal rhabdomyosarcoma (EM-bree-on-al RAB-do-MY-oh-sar-KO-ma)
A soft-tissue tumor that affects children. It begins in muscle cells, and usually occurs in the head, neck, arms, legs, or genitourinary tract.

embryonal tumor
A mass of rapidly growing cells that begins in embryonic (fetal) tissue. Embryonal tumors may be benign or malignant, and include neuroblastomas and Wilms' tumors. Also called embryoma.

embryonic
Having to do with an embryo, which is an early stage in the development of a plant or animal.

EMD 121974
A substance that is being studied as an anticancer and antiangiogenesis drug. Also called cilengitide.

EMD 72000
A monoclonal antibody that is being studied in the treatment of some types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. EMD 72000 binds to the epithelial growth factor receptor (EGFR) on tumor cells and blocks growth signals. Also called matuzumab.

emesis (EH-meh-siss)
Vomiting.

emetic (eh-MEH-tik)
Describes a substance that causes vomiting. Also called emetogenic.

emetogenic (eh-MEH-toh-JEN-ik)
Describes a substance that causes vomiting. Also called emetic.

emitefur
An anticancer drug that belongs to the family of drugs called antimetabolites.

emodin
A substance found in certain plants, including rhubarb. It belongs to a family of compounds called anthraquinones, which have shown anti-inflammatory and anticancer effects.

emphysema
Pulmonary emphysema is a disorder affecting the alveoli (tiny air sacs) of the lungs. The transfer of oxygen and carbon dioxide in the lungs takes place in the walls of the alveoli. In emphysema, the alveoli become abnormally inflated, damaging their walls and making it harder to breathe. People who smoke or have chronic bronchitis have an increased risk of emphysema.

enalapril
An antihypertensive agent that can also be used to slow or prevent the progression of heart disease in people with childhood cancer treated with drugs that may be harmful to the heart.

encapsulated (en-KAP-soo-lay-ted)
Confined to a specific, localized area and surrounded by a thin layer of tissue.

encephalopathy
A disorder of the brain that can be caused by disease, injury, drugs, or chemicals.

enchondroma (en-kon-DRO-ma)
A benign (noncancerous) growth of cartilage in bones or in other areas where cartilage is not normally found.

endocervical curettage (en-do-SER-vih-kul kyoo-reh-TAHZH)
A procedure in which the mucous membrane of the cervical canal is scraped using a spoon-shaped instrument called a curette.

endocrine (EN-doh-krin)
Refers to tissue that makes and releases hormones that travel in the bloodstream and control the actions of other cells or organs. Some examples of endocrine tissues are the pituitary, thyroid, and adrenal glands.

endocrine cancer
Cancer that occurs in endocrine tissue, the tissue in the body that secretes hormones.

endocrine pancreas cell
A pancreatic cell that produces hormones (e.g., insulin and glucagon) that are secreted into the bloodstream. These hormones help control the level of glucose (sugar) in the blood. Also called an islet cell and an islet of Langerhans cell.

endocrine system (EN-doh-krin SIS-tum)
A system of glands and cells that make hormones that are released directly into the blood and travel to tissues and organs all over the body. The endocrine system controls growth, sexual development, sleep, hunger, and the way the body uses food.

endocrine therapy (EN-doh-krin THAYR-uh-pee)
Treatment that adds, blocks, or removes hormones. For certain conditions (such as diabetes or menopause), hormones are given to adjust low hormone levels. To slow or stop the growth of certain cancers (such as prostate and breast cancer), synthetic hormones or other drugs may be given to block the body's natural hormones. Sometimes surgery is needed to remove the gland that makes a certain hormone. Also called hormone therapy, hormonal therapy, or hormone treatment.

endocrinologist (en-do-krih-NAH-lo-jist)
A doctor who specializes in diagnosing and treating hormone disorders.

endogenous
Produced inside an organism or cell. The opposite is external (exogenous) production.

endometrial
Having to do with the endometrium (the layer of tissue that lines the uterus).

endometrial biopsy
A procedure in which a sample of tissue is taken from the endometrium (inner lining of the uterus) for examination under a microscope. A thin tube is inserted through the cervix into the uterus, and gentle scraping and suction are used to remove the sample.

endometrial cancer (EN-doh-MEE-tree-ul KAN-ser)
Cancer that forms in the tissue lining the uterus. Most endometrial cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids).

endometrial disorder
Abnormal cell growth in the endometrium (the lining of the uterus).

endometrial hyperplasia
An abnormal overgrowth of the endometrium (the layer of cells that lines the uterus). There are four types of endometrial hyperplasia: simple endometrial hyperplasia, complex endometrial hyperplasia, simple endometrial hyperplasia with atypia, and complex endometrial hyperplasia with atypia. These differ in terms of how abnormal the cells are and how likely it is that the condition will become cancerous.

endometriosis (en-do-mee-tree-O-sis)
A benign condition in which tissue that looks like endometrial tissue grows in abnormal places in the abdomen.

endometrium (en-do-MEE-tree-um)
The layer of tissue that lines the uterus.

endorectal ultrasound (en-doh-REK-tul...)
ERUS. A procedure in which a probe that sends out high-energy sound waves is inserted into the rectum. The sound waves are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissue called a sonogram. ERUS is used to look for abnormalities in the rectum and nearby structures, including the prostate. Also called transrectal ultrasound.

endorphin (en-DOR-fin)
A morphine-like chemical that is made naturally in the brain and relieves pain.

endoscope (EN-doh-SKOPE)
A thin, tube-like instrument used to look at tissues inside the body. An endoscope has a light and a lens for viewing and may have a tool to remove tissue.

endoscopic retrograde cholangiopancreatography (en-doh-SKAH-pik REH-troh-grayd koh-LAN-jee-oh-PAN-kree-uh-TAH-gruh-fee)
ERCP. A procedure that uses an endoscope to examine and x-ray the pancreatic duct, hepatic duct, common bile duct, duodenal papilla, and gallbladder. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. The endoscope is passed through the mouth and down into the first part of the small intestine (duodenum). A smaller tube (catheter) is then inserted through the endoscope into the bile and pancreatic ducts. A dye is injected through the catheter into the ducts, and an x-ray is taken.

endoscopic ultrasound (en-doh-SKAH-pik...)
EUS. A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument that has a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal organs to make a picture (sonogram). Also called endosonography.

endoscopy (en-DOSS-koh-pee)
A procedure that uses an endoscope to examine the inside of the body. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.

endosonography
A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument that has a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal organs to make a picture (sonogram). Also called endoscopic ultrasound (EUS).

endostatin
A drug that is being studied for its ability to prevent the growth of new blood vessels into a solid tumor. Endostatin belongs to the family of drugs called angiogenesis inhibitors.

endothelial cell
The main type of cell found in the inside lining of blood vessels, lymph vessels, and the heart.

endothelin receptor antagonist
A drug that blocks the hormone endothelin and may prevent prostate cancer from spreading to the bones. It may also prevent the growth and spread of other types of cancer, including colorectal cancer.

endothelin-1 protein receptor antagonist
A substance that blocks the binding of the endothelin-1 protein to its receptor. Endothelin-1 is a small molecule that causes changes in blood vessels and helps regulate blood pressure. It can also stimulate the growth of some types of cells.

endpoint
In clinical trials, an event or outcome that can be measured objectively to determine whether the intervention being studied is beneficial. The endpoints of a clinical trial are usually included in the study objectives. Some examples of endpoints are survival, improvements in quality of life, relief of symptoms, and disappearance of the tumor.

enema
The injection of a liquid through the anus into the large bowel.

energy balance (EH-nur-jee BA-lunts)
In biology, the state at which the number of calories eaten equals the number of calories used. Energy balance is affected by physical activity, body size, amount of body fat and muscle, and genetics.

English lavender (...LA-vun-der)
A plant with aromatic leaves and flowers that is a member of the mint family. Oil from the flowers has been used in some cultures to treat certain medical problems, to keep insects away, and to wash in. It is also used in aromatherapy. Perillyl alcohol, a substance found in English lavender, is being studied in cancer prevention and treatment. Also called lavender and true lavender. The scientific name is Lavandula angustifolia.

eniluracil
An anticancer drug that increases the effectiveness of fluorouracil. Also called ethynyluracil.

enoxaparin
A drug used to prevent blood clots. It belongs to the family of drugs called anticoagulants.

ENT
A doctor who specializes in treating diseases of the ear, nose, and throat. Also called an otolaryngologist.

Entelev
A liquid that has been promoted as a treatment for a wide range of diseases, including cancer. The ingredients thought to be in Entelev have been tested, and none of them has been shown to be effective in treating any form of cancer. Entelev is not available in the United States. Also called Cancell, Sheridan's Formula, Jim's Juice, Crocinic Acid, JS'114, JS'101, 126'F, and Cantron.

enteral nutrition
A form of nutrition that is delivered into the digestive system as a liquid. Drinking nutrition beverages or formulas and tubefeeding are forms of enteral nutrition. People who are unable to meet their needs with food and beverages alone, and who do not have vomiting or uncontrollable diarrhea may be given tubefeedings. Tubefeeding can be used to add to what a person is able to eat or can be the only source of nutrition. A small feeding tube may be placed through the nose into the stomach or the small intestine, or it may be surgically placed into the stomach or the intestinal tract through an opening made on the outside of the abdomen, depending on how long it will be used.

enterostomal therapist (en-ter-o-STO-mul)
A health professional trained in the care of persons with stomas, such as colostomies or urostomies.

enucleation
In medicine, the removal of an organ or tumor in such a way that it comes out clean and whole, like a nut from its shell.

enveloped virus
A virus that has an outer wrapping or envelope. This envelope comes from the infected cell, or host, in a process called "budding off." During the budding process, newly formed virus particles become "enveloped" or wrapped in an outer coat that is made from a small piece of the cell's plasma membrane. The envelope may play a role in helping a virus survive and infect other cells.

environmental tobacco smoke
ETS. Smoke that comes from the burning of a tobacco product and smoke that is exhaled by smokers (second-hand smoke). Inhaling ETS is called involuntary or passive smoking.

enzastaurin
A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called protein kinase C inhibitors and angiogenesis inhibitors. Also called LY317615.

enzyme
A protein that speeds up chemical reactions in the body.

eosinophil
A type of white blood cell.

eosinophilia
A condition in which the number of eosinophils (a type of white blood cell) in the blood is greatly increased. Eosinophilia is often a response to infection or allergens (substances that cause an allergic response).

EP-2101
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called cancer vaccines.

ependymal tumor
A brain tumor that usually begins in the central canal of the spinal cord. Ependymal tumors may also develop in the cells lining the ventricles of the brain, which produce and store the special fluid (cerebrospinal fluid) that protects the brain and spinal cord. Also called an ependymoma.

ependymoma (ep-en-dih-MOE-mah)
A type of brain tumor that may arise in the ventricles of the brain or in the spinal cord. Also called an ependymal tumor.

ephedra (eh-FEH-druh)
Ephedra sinica. A shrub native to China and India. The stems and roots are used in traditional medicine as a diuretic and for asthma, bronchitis, and cough. It has also been promoted as a decongestant, a weight loss aid, and as a supplement to increase energy. Ephedra may cause high blood pressure, increased heart rate, or death if used with certain drugs, and may reduce the effects of certain drugs used to treat cancer and other diseases. The U.S. Food and Drug Administration has banned the sale of dietary supplements that contain ephedra. Also called ma huang.

epidemiology
The study of the patterns, causes, and control of disease in groups of people.

epidermal growth factor receptor
EGFR. The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide. It is found at abnormally high levels on the surface of many types of cancer cells, so these cells may divide excessively in the presence of epidermal growth factor. Also known as ErbB1 or HER1.

epidermis (ep-i-DER-mis)
The upper or outer layer of the two main layers of tissue that make up the skin.

epidermoid carcinoma (EH-pih-DUR-moyd KAHR-sih-NOH-muh)
Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the lining of the respiratory and digestive tracts. Also called squamous cell carcinoma.

epidural
Having to do with the space between the wall of the spinal canal and the covering of the spinal cord. An epidural injection is given into this space.

epidural block
An injection of an anesthetic drug into the space between the wall of the spinal canal and the covering of the spinal cord.

epigastric
Having to do with the upper middle area of the abdomen.

epiglottis (ep-ih-GLAH-tis)
The flap that covers the trachea during swallowing so that food does not enter the lungs.

epilepsy
A group of disorders marked by problems in the normal functioning of the brain. These problems can produce seizures, unusual body movements, a loss of consciousness or changes in consciousness, as well as mental problems or problems with the senses.

epinephrine
A hormone and neurotransmitter. Also called adrenaline.

epipodophyllotoxin
A drug used to treat a variety of childhood cancers. Epipodophyllotoxins belong to a larger class of drugs called topoisomerase II inhibitors.

epirubicin
An anticancer drug that belongs to the family of drugs called antitumor antibiotics. It is an anthracycline.

epithelial (ep-ih-THEE-lee-ul)
Refers to the cells that line the internal and external surfaces of the body.

epithelial carcinoma (ep-ih-THEE-lee-ul KAR-sih-NOH-muh)
Cancer that begins in the cells that line an organ.

epithelial ovarian cancer (ep-ih-THEE-lee-ul)
Cancer that occurs in the cells lining the ovaries.

epithelium (EP-ih-THEE-lee-um)
A thin layer of tissue that covers organs, glands, and other structures within the body.

epitope (EP-i-tope)
A part of a molecule that an antibody will recognize and bind to.

EPO906
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called epothilones. Also called epothilone B.

epoetin alfa
A substance that is made in the laboratory that stimulates the bone marrow to make red blood cells. It belongs to the family of drugs called antianemics. It is also called recombinant human erythropoietin.

epoetin beta
A substance that is made in the laboratory and that stimulates the bone marrow to make red blood cells. It belongs to the family of drugs called antianemics. It is also called recombinant human erythropoietin.

epothilone
A drug obtained from bacteria that interferes with cell division. Some epothilones are being studied as treatments for cancer.

epothilone B
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called epothilones. Also called EPO906.

epothilone D
A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called mitotic inhibitors and epothilones. Also called KOS-862.

epratuzumab
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called radiolabeled monoclonal antibodies.

Epstein-Barr virus
EBV. A common virus that remains dormant in most people. It has been associated with certain cancers, including Burkitt's lymphoma, immunoblastic lymphoma, and nasopharyngeal carcinoma.

EPT
Electroporation therapy. Treatment that generates electrical pulses through an electrode placed in a tumor to enhance the ability of anticancer drugs to enter tumor cells.

ER
Estrogen receptor. Protein found on some cancer cells to which estrogen will attach.

ER+
Estrogen receptor positive. Describes cells that have a protein to which the hormone estrogen will bind. Cancer cells that are ER+ need estrogen to grow, and may stop growing when treated with hormones that block estrogen from binding.

ER-
Estrogen receptor negative. Describes cells that do not have a protein to which the hormone estrogen will bind. Cancer cells that are ER- do not need estrogen to grow, and usually do not stop growing when treated with hormones that block estrogen from binding.

ERA-923
A substance that is being studied as a treatment for cancer. It belongs to a family of drugs called antiestrogens.

erb-38 immunotoxin
A toxic substance linked to an antibody that attaches to tumor cells and kills them.

ErbB1
Epidermal growth factor receptor. The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide. It is found at abnormally high levels on the surface of many types of cancer cells, so these cells may divide excessively in the presence of epidermal growth factor. Also known as EGFR or HER1.

Erbitux (er-bih-TUX)
A monoclonal antibody used to treat some types of head and neck cancer, and colorectal cancer that has spread to other parts of the body. It is also being studied in the treatment of other types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. Also called cetuximab.

ERCP
Endoscopic retrograde cholangiopancreatography. A procedure that uses an endoscope to examine and x-ray the pancreatic duct, hepatic duct, common bile duct, duodenal papilla, and gallbladder. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. The endoscope is passed through the mouth and down into the first part of the small intestine (duodenum). A smaller tube (catheter) is then inserted through the endoscope into the bile and pancreatic ducts. A dye is injected through the catheter into the ducts, and an x-ray is taken.

erectile dysfunction
An inability to have an erection of the penis adequate for sexual intercourse. Also called impotence.

erection (ih-REK-shun)
In medicine, the swelling of the penis with blood, causing it to become firm.

erlotinib
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called epidermal growth factor receptor tyrosine kinase inhibitors. Also called CP-358,774 and OSI-774.

ERT
Estrogen replacement therapy. Hormones (estrogen, progesterone, or both) given to postmenopausal women or to women who have had their ovaries surgically removed. Hormones are given to replace the estrogen no longer produced by the ovaries.

ERUS
Endorectal ultrasound. A procedure in which a probe that sends out high-energy sound waves is inserted into the rectum. The sound waves are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissue called a sonogram. ERUS is used to look for abnormalities in the rectum and nearby structures, including the prostate. Also called transrectal ultrasound.

erythema
Redness of the skin.

erythrocyte (eh-RITH-ro-site)
A cell that carries oxygen to all parts of the body. Also called a red blood cell (RBC).

erythrocyte sedimentation rate
ESR. The distance red blood cells travel in one hour in a sample of blood as they settle to the bottom of a test tube. The sedimentation rate is increased in inflammation, infection, cancer, rheumatic diseases, and diseases of the blood and bone marrow. Also called sedimentation rate.

erythrodysplasia
A condition in which immature red blood cells (erythroid cells) in the bone marrow are abnormal in size, shape, organization, and/or number. Erythrodysplasia may be caused by vitamin deficiency or chemotherapy, or it may be a sign of refractory anemia, which is a myelodysplastic syndrome. Also called erythroid dysplasia.

erythroid dysplasia
A condition in which immature red blood cells (erythroid cells) in the bone marrow are abnormal in size, shape, organization, and/or number. Erythroid dysplasia may be caused by vitamin deficiency or chemotherapy, or it may be a sign of refractory anemia, which is a myelodysplastic syndrome. Also called erythrodysplasia.

erythroleukemia (eh-RITH-ro-loo-KEE-mee-a)
Cancer of the blood-forming tissues in which large numbers of immature, abnormal red blood cells are found in the blood and bone marrow.

erythroleukoplakia (eh-RITH-ro-LOO-ko-PLAY-kee-a)
An abnormal patch of red and white tissue that forms on mucous membranes in the mouth and may become cancerous. Tobacco (smoking or chewing) and alcohol may increase the risk of erythroleukoplakia.

erythroplakia (eh-RITH-ro-PLAY-kee-a)
An abnormal patch of red tissue that forms on mucous membranes in the mouth and may become cancerous. Tobacco (smoking and chewing) and alcohol may increase the risk of erythroplakia.

erythropoietin
A substance that is naturally produced by the kidneys, and that stimulates the bone marrow to make red blood cells. When erythropoietin is made in the laboratory, it is called epoetin alfa or epoetin beta.

escitalopram (es-sy-TAL-oh-pram)
A drug used to treat depression and certain anxiety disorders. It belongs to the family of drugs called selective serotonin reuptake inhibitors (SSRIs). Also called Lexapro.

esophageal (ee-SOF-uh-jee-ul)
Having to do with the esophagus, the muscular tube through which food passes from the throat to the stomach.

esophageal cancer (ee-SOF-uh-jee-ul KAN-ser)
Cancer that forms in tissues lining the esophagus (the muscular tube through which food passes from the throat to the stomach). Two types of esophageal cancer are squamous cell carcinoma (cancer that begins in flat cells lining the esophagus) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids).

esophageal reflux (ee-SOF-uh-jee-al REE-flux)
The backward flow of stomach acid contents into the esophagus (the tube that connects the mouth to the stomach). Also called gastroesophageal reflux or gastric reflux.

esophageal speech (ee-SOF-uh-jee-al...)
Speech produced by trapping air in the esophagus and forcing it out again. It is used after removal of a person's larynx (voice box).

esophagectomy (ee-sof-uh-JEK-tuh-mee)
An operation to remove a portion of the esophagus.

esophagitis
Inflammation of the esophagus (the tube that carries food from the mouth to the stomach).

esophagoscopy (ee-sof-uh-GOSS-koh-pee)
Examination of the esophagus using an esophagoscope. An esophagoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.

esophagram (ee-SOF-uh-gram)
A series of x-rays of the esophagus. The x-ray pictures are taken after the person drinks a solution that contains barium. The barium coats and outlines the esophagus on the x-ray. Also called a barium swallow and upper GI series.

esophagus (ee-SOF-uh-gus)
The muscular tube through which food passes from the throat to the stomach.

ESR
erythrocyte sedimentation rate. The distance red blood cells travel in one hour in a sample of blood as they settle to the bottom of a test tube. The sedimentation rate is increased in inflammation, infection, cancer, rheumatic diseases, and diseases of the blood and bone marrow. Also called sedimentation rate.

essential oil (eh-SENT-shul...)
The scented liquid taken from some plants using steam or pressure. Essential oils are used in perfumes, soaps, and aromatherapy.

essential thrombocythemia
An increased number of thrombocytes (platelets) in the blood, without a known cause. Also called essential thrombocytosis.

essential thrombocytosis
An increased number of thrombocytes (platelets) in the blood, without a known cause. Also called essential thrombocythemia.

Essiac
An herbal tea mixture that contains burdock root, Indian rhubarb root, sheep sorrel, and slippery elm bark. It has been claimed to remove toxins from the body, make the immune system stronger, relieve pain, control diabetes, treat AIDS, reduce tumor size, increase cancer survival, and improve quality of life. No clinical trial using Essiac in humans has been reported in a peer-reviewed, scientific journal, and the FDA has not approved the use of Essiac for the treatment of any medical conditions.

ester (ES-ter)
A type of chemical substance that is a combination of acid and alcohol. Esters are found in essential oils (scented liquid taken from plants).

esterified estrogen (eh-STAYR-uh-fide ES-truh-jin)
A form of estrogen that may have fewer side effects than other forms. Esterified estrogens are used to treat some types of cancer, including prostate cancer. They are also used to treat the symptoms of menopause, (such as hot flashes, vaginal dryness, or heavy and painful bleeding) and osteoporosis (loss of bone mass). They belong to the family of drugs called hormone therapies.

estradiol (es-truh-DY-ol)
A form of the hormone estrogen.

estramustine
A combination of the hormone estradiol (an estrogen) and nitrogen mustard (an anticancer drug). Used in the palliative therapy of prostate cancer.

estrogen (ES-truh-jin)
A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones. Estrogens can also be made in the laboratory. They may be used as a type of birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other disorders.

estrogen receptor (ES-truh-jin)
A protein found inside the cells of the female reproductive tissue, some other types of tissue, and some cancer cells. The hormone estrogen will bind to the receptors inside the cells and may cause the cells to grow.

estrogen receptor negative (ES-truh-jin rih-SEP-ter NEH-guh-tiv)
ER-. Describes cells that do not have a protein to which the hormone estrogen will bind. Cancer cells that are ER- do not need estrogen to grow, and usually do not stop growing when treated with hormones that block estrogen from binding.

estrogen receptor positive (ES-truh-jin rih-SEP-ter PAH-zuh-tiv)
ER+. Describes cells that have a protein to which the hormone estrogen will bind. Cancer cells that are ER+ need estrogen to grow, and may stop growing when treated with hormones that block estrogen from binding.

estrogen receptor test (ES-truh-jin rih-SEP-ter test)
A lab test to find out if cancer cells have estrogen receptors (proteins to which estrogen will bind). If the cells have estrogen receptors, they may need estrogen to grow, and this may affect how the cancer is treated.

estrogen replacement therapy (ES-truh-jin rih-PLAYSS-munt THAYR-uh-pee)
ERT. Hormones (estrogen, progesterone, or both) given to postmenopausal women or to women who have had their ovaries surgically removed. Hormones are given to replace the estrogen no longer produced by the ovaries.

etanercept
A drug that is commonly used to treat arthritis. It is also being studied in the treatment of cancer, and as a treatment for loss of appetite and weight loss in cancer patients. It belongs to the family of drugs called tumor necrosis factor (TNF) antagonists.

etanidazole
A drug that increases the effectiveness of radiation therapy.

ethical will (EH-thih-kul will)
A final personal message or document in which a person shares his or her thoughts, values, memories, life lessons, advice, and hopes for the future. The person may also ask for forgiveness and forgive others. An ethical will is not a legal document.

ethynyluracil
An anticancer drug that increases the effectiveness of fluorouracil. Also called eniluracil.

etidronate
A drug that belongs to the family of drugs called bisphosphonates. Bisphosphonates are used as treatment for hypercalcemia (abnormally high levels of calcium in the blood) and for cancer that has spread to the bone (bone metastases).

etiology
The cause or origin of disease.

etoposide
An anticancer drug that belongs to the families of drugs called podophyllotoxin derivatives and topoisomerase inhibitors.

etoposide phosphate (e-TOPE-o-side FOS-fate)
A drug that is used to treat testicular and small cell lung cancers, and is being studied in the treatment of other cancers. It belongs to the families of drugs called podophyllotoxin derivatives and topoisomerase inhibitors. Also called Etopophos.

ETS
Environmental tobacco smoke. Smoke that comes from the burning of a tobacco product and smoke that is exhaled by smokers (second-hand smoke). Inhaling ETS is called involuntary or passive smoking.

eucalyptus (YOO-kuh-LIP-tus)
A type of evergreen tree that is a member of the myrtle family. Oil from the leaves is used in very small amounts in mouthwash and in medicines and candy used to treat and soothe sore throats and coughs. It has also been used in some cultures to treat many other medical problems. The scientific name is Eucalyptus globulus.

euphoria (yoo-FOR-ee-uh)
A feeling of great happiness or well-being. Euphoria may be a side effect of certain drugs.

EUS
Endoscopic ultrasound. A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument that has a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal organs to make a picture (sonogram). Also called endosonography.

euthanasia (YOO-thuh-NAY-zhuh)
An easy or painless death, or the intentional ending of the life of a person suffering from an incurable or painful disease at his or her request. Also called mercy killing.

evaluable disease
Disease that cannot be measured directly by the size of the tumor but can be evaluated by other methods specific to a particular clinical trial.

evaluable patients
Patients whose response to a treatment can be measured because enough information has been collected.


Evaluated
The providers will check you thoroughly to make certain you don't have cancer. This may include blood tests and taking additional X-ray pictures, MRIs or views of your breasts,
everolimus
A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called immunosuppressive agents and antiangiogenesis agents.

Ewing's family of tumors
EFTs. A group of cancers that includes Ewing's tumor of bone (ETB or Ewing's sarcoma of bone), extraosseus Ewing's (EOE) tumors, primitive neuroectodermal tumors (PNET or peripheral neuroepithelioma), and Askin's tumors (PNET of the chest wall). These tumors all come from the same type of stem cell.

Ewing's sarcoma (YOO-ingz sar-KO-ma)
A type of bone cancer that usually forms in the middle (shaft) of large bones. Also called Ewing's sarcoma/primitive neuroectodermal tumor (PNET).

ex vivo (ex VEE-voh)
Outside of the living body. Refers to a medical procedure in which an organ, cells, or tissue are taken from a living body for a treatment or procedure, and then returned to the living body.

exatecan mesylate
An anticancer drug that belongs to the family of drugs called topoisomerase inhibitors. Also called DX-8951f.

excision (ek-SIH-zhun)
Removal by surgery.

excisional biopsy (ek-SI-zhun-al BY-op-see)
A surgical procedure in which an entire lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

excisional skin surgery (ek-SIH-zhun-al SER-juh-ree)
A surgical procedure used to remove moles, cysts, skin cancer, and other skin growths using local anesthesia. To treat skin cancer, the doctor uses a scalpel to remove the entire tumor and some of the healthy tissue around it.

exemestane
An anticancer drug used to decrease estrogen production and suppress the growth of estrogen-dependent tumors.

exenteration (ek-ZEN-ter-AY-shun)
Surgery to remove organs within a body cavity.

exisulind
A drug that is being studied in the treatment and prevention of cancer. It has been shown to cause apoptosis (cell death) in cancerous and precancerous cells by acting through a group of cellular enzymes called cGMP phosphodiesterases.

exocrine cancer (EK-suh-krin KAN-ser)
A type of pancreatic cancer in which malignant (cancer) cells are found in the non-insulin producing tissues of the pancreas.

exocrine pancreas cell
A pancreatic cell that produces enzymes that are secreted into the small intestine. These enzymes help digest food as it passes through the gastrointestinal tract.

expanded access trial
A way to provide an investigational therapy to a patient who is not eligible to receive that therapy in a clinical trial, but who has a serious or life-threatening illness for which other treatments are not available. Expanded access allows a patient to receive promising but not yet fully studied or approved cancer therapies when no other treatment option exists. Also called compassionate use trial.

experimental
In clinical trials, refers to a drug (including a new drug, dose, combination, or route of administration) or procedure that has undergone basic laboratory testing and received approval from the US Food and Drug Administration (FDA) to be tested in human subjects. A drug or procedure may be approved by the FDA for use in one disease or condition, but be considered experimental in other diseases or conditions. Also called investigational.

experimental drug
A substance that has been tested in a laboratory and has gotten approval from the U.S. Food and Drug Administration (FDA) to be tested in people. A drug may be approved by the FDA for use in one disease or condition but be considered experimental in other diseases or conditions. Also called an investigational drug.

extensive-stage small cell lung cancer
Cancer has spread outside of the lung in which it began or to other parts of the body.

external radiation (ray-dee-AY-shun)
Radiation therapy that uses a machine to aim high-energy rays at the cancer. Also called external-beam radiation.

external-beam radiation (ray-dee-AY-shun)
Radiation therapy that uses a machine to aim high-energy rays at the cancer. Also called external radiation.

extracorporeal photopheresis (EK-struh-kore-PORE-ee-ul FOH-toh-fuh-REE-siss)
A procedure in which blood is removed from the body and treated with ultraviolet light and drugs that become active when exposed to light. The blood is then returned to the body. It is being studied in the treatment of some blood and bone marrow diseases and graft-vs-host disease (GVHD). Also called photopheresis.

extracranial (EK-struh-KRAY-nee-ul)
Outside of the cranium (bones that surround the brain).

extracranial germ cell tumor (EK-struh-KRAY-nee-ul jurm sel TOO-mer)
A rare cancer that forms in germ cells in the testicle or ovary, or in germ cells that have traveled to areas of the body other than the brain (such as the chest, abdomen, or tailbone). Germ cells are reproductive cells that develop into sperm in males and eggs in females.

extract (EK-strakt)
In medicine, a preparation of a substance obtained from plants, animals, or bacteria and used as a drug or in drugs.

extragonadal germ cell tumor (EK-struh-go-NA-dul jurm sel TOO-mer)
A rare cancer that develops in germ cells that are found in areas of the body other than the ovary or testicle (such as the brain, chest, abdomen, or tailbone). Germ cells are reproductive cells that develop into sperm in males and eggs in females.

extrahepatic (EK-struh-hih-PA-tik)
Located or occurring outside the liver.

extrahepatic bile duct (EK-struh-hih-PA-tik BILE dukt)
The part of the common hepatic bile duct (tube that collects bile from the liver) that is outside the liver. This duct joins a duct from the gallbladder to form the common bile duct, which carries bile into the small intestine when food is being digested.

extrapleural pneumonectomy
Surgery to remove a diseased lung, part of the pericardium (membrane covering the heart), part of the diaphragm (muscle between the lungs and the abdomen), and part of the parietal pleura (membrane lining the chest). This type of surgery is used most often to treat malignant mesothelioma.

eye cancer (I KAN-ser)
Cancer that forms in tissues of and around the eye. Some of the cancers that may affect the eye include melanoma (a rare cancer that begins in cells that make the pigment melanin in the eye), carcinoma (cancer that begins in tissues that cover structures in the eye), lymphoma (cancer that begins in immune system cells), and retinoblastoma (cancer that begins in the retina and usually occurs in children younger than 5 years).


top of page