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531 results found for:   
  C



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-ABL  
An enzyme that is involved in many cell processes, such as cell division. The gene for c-ABL is on chromosome 9. In most patients with chronic myelogenous leukemia (CML), the part of chromosome 9 with c-ABL has broken off and traded places with part of chromosome 22 to form the BCR-ABL fusion gene.

c-erbB-2  
A protein involved in normal cell growth. It is found in high levels on some breast cancer cells. Also called HER2/neu and human epidermal growth factor receptor 2.

c-kit receptor  (... reh-SEP-ter)
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 that may be found in high amounts in the blood of patients with certain types of cancer, including ovarian cancer. CA-125 levels may also help monitor how well cancer treatments are working or if cancer has come back. Also called cancer antigen 125.

CAB  
Surgery in which a healthy blood vessel taken from another part of the body is used to make a new path for blood around a blocked artery leading to the heart. This restores the flow of oxygen and nutrients to the heart. Also called aortocoronary bypass and coronary artery bypass.

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 artery disease and 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.

caffeine  (ka-FEEN)
A substance found in the leaves and beans of the coffee tree, in tea, yerba mate, guarana berries, and in small amounts in cocoa. It can also be made in the laboratory, and is added to some soft drinks, foods, and medicines. Caffeine increases brain activity, alertness, attention, and energy. It may also increase blood pressure, heart rate, breathing rate, and the loss of water from the body in urine.

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  (KAL-sih-TOH-nin)
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.

calcium gluconate  (KAL-see-um GLOO-koh-nayt)
The mineral calcium, combined with a form of the sugar glucose. It is used to prevent and treat bone loss. It is also being studied in the treatment of bone loss and nerve damage caused by chemotherapy.

calcium levoleucovorin  (KAL-see-um LEE-voh-LOO-koh-VOR-in)
A drug used to reduce the toxic effects of folic acid antagonists (substances that block the action of folic acid), especially the anticancer drug methotrexate. It is also used to treat anemia and it is used with fluorouracil to treat symptoms of advanced colorectal cancer. It is also being studied in the treatment of other types of cancer and other conditions. Calcium levoleucovorin is a form of folic acid, a B-complex vitamin that the body needs to make red blood cells and to function and stay healthy. Calcium levoleucovorin is a type of chemoprotective agent and a type of chemosensitizing agent. Also called leucovorin calcium and Wellcovorin.

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.

calgranulin A  (kal-GRAN-yoo-lin ...)
A protein that is made by many different types of cells and is involved in processes that take place both inside and outside of the cell. It is made in larger amounts in inflammatory diseases such as rheumatoid arthritis, and in some types of cancer. It is being studied as a biomarker for breast cancer. Also called S100 calcium binding protein A8.

calgranulin B  (kal-GRAN-yoo-lin ...)
A protein that is made by many different types of cells and is involved in processes that take place both inside and outside of the cell. It is made in larger amounts in inflammatory diseases such as rheumatoid arthritis, and in some types of cancer. It is being studied as a biomarker for breast cancer. Also called S100 calcium binding protein A9.

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

calorie  (KA-luh-ree)
A measurement of the energy content of food. The body needs calories as to perform 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  
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. Also called complementary and alternative medicine.

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 126–F, Cantron, Crocinic Acid, Jim’s Juice, JS–101, JS–114, Protocel, and Sheridan’s Formula.

cancer  (KAN-ser)
A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. 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 blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

cancer antigen 125  (KAN-ser AN-tih-jen...)
A substance that may be found in high amounts in the blood of patients with certain types of cancer, including ovarian cancer. Cancer antigen 125 levels may also help monitor how well cancer treatments are working or if cancer has come back. Also called CA-125.

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  
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. Also called CIS.

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. Also called carcinoma of unknown primary and CUP.

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. Candidiasis usually affects the mouth (oral candidiasis); however, rarely, it spreads throughout the entire body. Also called candidosis and 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. Candidosis usually affects the mouth (oral candidosis); however, rarely, it spreads throughout the entire body. Also called candidiasis and thrush.

canertinib  (can-ER-tih-nib)
A substance being studied in the treatment of some types of cancer. Canertinib blocks the action of proteins called epidermal growth factor receptors, and may cause cancer cells to die. It is a type of tyrosine kinase inhibitor. Also called canertinib dihydrochloride and CI-1033.

canertinib dihydrochloride  (can-ER-tih-nib dy-HY-droh-KLOR-ide)
A substance being studied in the treatment of some types of cancer. Canertinib dihydrochloride blocks the action of proteins called epidermal growth factor receptors, and may cause cancer cells to die. It is a type of tyrosine kinase inhibitor. Also called canertinib and CI-1033.

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 126–F, Cancell, Crocinic Acid, Jim’s Juice, JS–101, JS–114, Protocel, and Sheridan’s Formula.

CAP-1  
A protein that can stimulate an immune response. Also called carcinoembryonic antigen peptide-1.

capecitabine  (ka-peh-SITE-uh-been)
A drug used to treat stage III colon cancer in patients who had surgery to remove the cancer. It is also used to treat metastatic breast cancer that has not improved after treatment with certain other anticancer drugs. Capecitabine is being studied in the treatment of other types of cancer. It is taken up by cancer cells and breaks down into 5-fluorouracil, a substance that kills tumor cells. Capecitabine is a type of antimetabolite. Also called Xeloda.

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.

capromab pendetide  (KAP-roh-mab PEN-deh-tide)
A substance used to detect prostate cancer. It contains a monoclonal antibody that binds to prostate cells, linked to a substance that can bind radioisotopes. Capromab pendetide is combined with indium 111 and injected into the body. A gamma camera (a special camera that detects radioactivity) is used to find prostate cancer cells in the body. Capromab pendetide is a type of immunoconjugate. Also called ProstaScint.

capsaicin  (kap-SAY-ih-sin)
A component of certain plants, including cayenne and red pepper, used topically for peripheral nerve pain. It is 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.

carbamide  (KAR-buh-MIDE)
A substance formed by the breakdown of protein in the liver. The kidneys filter carbamide out of the blood and into the urine. Carbamide can also be made in the laboratory. A topical form of carbamide is being studied in the treatment of hand-foot syndrome (pain, swelling, numbness, tingling, or redness of the hands or feet that may occur as a side effect of certain anticancer drugs). Also called urea.

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-sid)
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 dioxide  (KAR-bun dy-OK-side)
A colorless, odorless gas. It is a waste product made by the body. Carbon dioxide travels in the blood from the body’s tissues to the lungs. Breathing out clears carbon dioxide from the lungs.

carbon monoxide  (KAR-bun muh-NOK-side)
A poisonous gas that has no color or odor. It is given off by burning fuel (as in exhaust from cars or household heaters) and tobacco products. Carbon monoxide prevents red blood cells from carrying enough oxygen for cells and tissues to live.

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

carboplatin  (KAR-boh-pla-tin)
A drug that is used to treat symptoms of ovarian cancer that has come back after treatment with other anticancer drugs or to treat advanced ovarian cancer that has never been treated. It is also used together with other anticancer drugs to treat non-small cell lung cancer and is being studied in the treatment of other types of cancer. Carboplatin is a form of cisplatin that causes fewer side effects in patients. It attaches to DNA (the molecules inside cells that carry genetic information and pass it from one generation to the next) and may cause cancer cells to die. It is a type of platinum compound.

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-sih-noh-EM-bree-AH-nik AN-tih-jen)
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. Also called CEA.

carcinoembryonic antigen peptide-1  (KAR-sih-noh-EM-bree-AH-nik AN-tih-jen PEP-tide-1)
A protein that can stimulate an immune response to certain tumors. Also called CAP-1.

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

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

carcinoid  (KAR-sih-noyd)
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-sih-noyd SIN-drome)
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 SY-too)
A group of abnormal cells that remain in the tissue in which they first formed. These abnormal cells may become cancer and spread into nearby normal tissue.

carcinoma of unknown primary  (KAR-sih-NOH-muh...)
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. Also called cancer of unknown primary origin and CUP.

carcinomatosis  (KAR-sih-NOH-muh-TOH-sis)
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.

carcinomatous meningitis  (KAR-sih-NOH-muh-tus MEH-nin-JY-tis)
Inflammation of the meninges (three thin layers of tissue that cover and protect the brain and spinal cord) caused by cancer that has spread there. Also called neoplastic meningitis.

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 pacemaker  (KAR-dee-AK PAYS-may-ker)
An electronic device that is implanted in the body to monitor heart rate and rhythm. It gives the heart electrical stimulation when it does not beat normally. It runs on batteries and has long, thin wires that connect it to the heart. Also called artificial pacemaker and pacemaker.

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

cardin  (KAR-din)
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. The scientific name is Cnicus benedictus. Also called blessed thistle, holy thistle, spotted thistle, and St. Benedict's thistle.

cardiopulmonary  
Having to do with the heart and lungs.

cardiotoxicity  (KAR-dee-oh-tok-SIH-sih-tee)
Toxicity that affects the heart.

cardiovascular  (KAR-dee-oh-VAS-kyoo-ler)
Having to do with the heart and blood vessels.

Cardura  (kar-DOO-ruh)
A drug used to treat high blood pressure and urinary problems caused by an enlarged prostate. It relaxes muscle tissue in blood vessels and in the prostate. Cardura is a type of alpha blocker. Also called doxazosin and doxazosin mesylate.

carina tracheae  (kuh-RY-nuh TRAY-kee-uh)
A ridge at the base of the trachea (windpipe) that separates the openings of the right and left main bronchi (the large air passages that lead from the trachea to the lungs).

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

Carney complex  (KAR-nee KOM-plex)
A rare, inherited disorder marked by dark spots on the skin and tumors in the heart, endocrine glands, skin, and nerves. There are two types of Carney complex, which are caused by mutations (changes) in different genes.

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...)
An 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 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 disease  (KA-sel-man dih-ZEEZ)
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  
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 scan, computerized axial tomography scan, computerized tomography, and CT scan.

CAT-8015  
A monoclonal antibody linked to a toxic substance. It is being studied in the treatment of some types of B-cell cancer. CAT-8015 is made in the laboratory. It binds to CD22, a protein on the surface of normal B cells and B-cell tumors, and kills the cells. Also called anti-CD22 immunotoxin CAT-8015.

Catapres  (KAT-uh-pres)
A drug used to treat high blood pressure. It is also being studied in the treatment of certain types of cancer pain. It blocks the release of chemicals from nerve endings that make blood vessels constrict (get narrower). Catapres is a type of antihypertensive agent and a type of alpha-adrenergic agonist. Also called clonidine hydrochloride.

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  (ka-tuh-KOL)
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 made in the laboratory.

catecholamine  (ka-tuh-KOH-luh-meen)
A type of neurohormone (a chemical that is made by nerve cells and used to send signals to other cells). Catecholamines are important in stress responses. High levels cause high blood pressure which can lead to headaches, sweating, pounding of the heart, pain in the chest, and anxiety. Examples of catecholamines include dopamine, epinephrine (adrenaline), and norepinephrine (noradrenaline).

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

cauterize  (KAW-teh-RIZE)
To destroy tissue using a hot or cold instrument, an electrical current, or a chemical that burns or dissolves the tissue. 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 hollow area or hole. It may describe a body cavity (such as the space within the abdomen) or a hole in a tooth caused by decay.

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 and complete blood count.

cBR96-doxorubicin immunoconjugate  (... DOK-soh-ROO-bih-sin IH-myoo-noh-KON-juh-gayt)
A substance 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. Doxorubicin is a type of anthracycline antitumor antibiotic. When it is combined with a monoclonal antibody, it forms a type of drug conjugate. Also called SGN-15.

CBT-1  
A substance taken from plants that is being studied in the treatment of cancer. It may help drugs kill tumor cells that have become resistant to drugs. It is a type of multidrug resistance inhibitor and a type of P-glycoprotein antagonist. Also called MDR modulator CBT-1.

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-4047  
A substance being studied in the treatment of prostate cancer, multiple myeloma, and other types of cancer. CC-4047 is a form of the drug thalidomide. It stops the growth of blood vessels, stimulates the immune system, and may kill cancer cells. CC-4047 is a type of angiogenesis inhibitor and a type of immunomodulatory agent. Also called Actimid and pomalidomide.

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 drug that is similar to thalidomide, and is used to treat multiple myeloma and certain types of anemia. It is also being studied in the treatment of other types of cancer. CC-5013 belongs to the family of drugs called angiogenesis inhibitors. Also called lenalidomide and Revlimid.

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 drug used to treat advanced renal cell carcinoma (a type of kidney cancer). It is also being studied in the treatment of other types of cancer. CCI-779 blocks a protein involved in cell division, and may kill cancer cells. It is a type of rapamycin analog and a type of serine/threonine kinase inhibitor. Also called temsirolimus and Torisel.

cCLB8  
A chimeric (made from human and mouse proteins) monoclonal antibody being studied in the treatment of advanced kidney cancer and other types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. cCLB8 works by blocking inflammation and tumor growth. Also called anti-IL-6 chimeric monoclonal antibody and CNTO 328.

CD134  
A protein being studied in the treatment of cancer. Substances that attach to CD134 on the surface of T cells (a type of white blood cell) may help the T cells grow and kill more cancer cells. CD134 is a type of tumor necrosis factor (TNF) receptor. Also called OX-40.

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.

CDDO  
A substance being studied in the treatment of some types of cancer. CDDO may block enzymes involved in inflammation and cancer growth. It is a type of antineoplastic plant product.

CDK inhibitor AT7519M  (... in-HIH-bih-ter ...)
A substance being studied in the treatment of some types of cancer. CDK inhibitor AT7519M blocks enzymes needed for cells to divide. It is a type of cyclin-dependent kinase inhibitor. Also called AT7519M.

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. Also called carcinoembryonic antigen.

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. The scientific name is Juniperus virginiana. Also called Eastern red cedar and red cedar.

cediranib  (seh-DIR-uh-nib)
A substance being studied in the treatment of some types of cancer. Cediranib blocks the growth of new blood vessels needed for tumors to grow and may kill cancer cells. It is a type of angiogenesis inhibitor and a type of vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor. Also called AZD2171 and Recentin.

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-uh-KOK-sib)
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  (sel)
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

cell culture  (SEL KUL-chur)
The growth of microorganisms such as bacteria and yeast, or human, plant, or animal cells in the laboratory. Cell cultures may be used to diagnose infections, to test new drugs, and in research.

cell cycle  (SEL SY-kul)
The process a cell goes through each time it divides. The cell cycle consists of a series of steps during which the chromosomes and other cell material double to make two copies. The cell then divides into two daughter cells, each receiving one copy of the doubled material. The cell cycle is complete when each daughter cell is surrounded by its own outer membrane. Also called mitotic cycle.

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  (SEL proh-LIH-fuh-RAY-shun)
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 aerobic metabolism, aerobic respiration, and oxidative metabolism.

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.

CellCept  (SEL-sept)
A drug used to prevent graft-versus-host disease (GVHD) after organ transplants. It is also being studied in the prevention of GVHD after stem cell transplants for cancer, and in the treatment of some autoimmune disorders. CellCept is a type of immunosuppressive agent. Also called mycophenolate mofetil.

cellular adhesion  (SEL-yoo-ler ad-HEE-zhun)
The close adherence (bonding) to adjoining cell surfaces.

cellular adoptive immunotherapy  (SEL-yoo-ler uh-DOP-tiv IH-myoo-noh-THAYR-uh-pee)
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  (SEL-yoo-ler meh-TA-buh-lih-zum)
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.

cellulose  (SEL-yoo-lose)
A building block of plant cells and fiber. Cellulose cannot be digested by people, and is used to add bulk to the diet.

centimeter  (SEN-tih-MEE-ter)
A measure of length in the metric system. There are 100 centimeters in a meter and 2½ centimeters in an inch.

central nervous system  (SEN-trul NER-vus SIS-tem)
The brain and spinal cord. Also called CNS.

central nervous system metastasis  (SEN-trul NER-vus SIS-tem meh-TAS-tuh-sis)
Cancer that has spread from the original (primary) tumor to the central nervous system (CNS). Also called CNS metastasis.

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

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

central nervous system sanctuary therapy  (SEN-trul NER-vus SIS-tem SANK-choo-WAYR-ee THAYR-uh-pee)
Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It kills cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called central nervous system prophylaxis, CNS prophylaxis, and CNS sanctuary therapy.

central nervous system tumor  (SEN-trul NER-vus SIS-tem TOO-mer)
A tumor of the central nervous system, including brain stem glioma, craniopharyngioma, medulloblastoma, and meningioma. Also called CNS tumor.

central venous access catheter  (SEN-trul VEE-nus AK-ses KA-theh-ter)
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  (... dy-HY-droh-KLOR-ide)
A substance being studied in the treatment of some types of cancer. CEP-2563 dihydrochloride blocks certain proteins involved in the growth of some tumors and may kill cancer cells. It is a type of receptor tyrosine kinase inhibitor.

CEP-701  
A drug being studied in the treatment of acute leukemias and some other types of cancer. It binds to a protein that is present on the surface of some types of cancer cells and stops them from dividing. CEP-701 is a type of receptor tyrosine kinase inhibitor and a type of indolocarbazole alkaloid. Also called lestaurtinib.

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  (ser-eh-BEH-ler hee-MAN-jee-OH-blas-TOH-muh)
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-broh-SPY-nul...)
The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin layers of tissue that cover and protect the brain and spinal cord). Cerebrospinal fluid is made by tissue called the choroid plexus in the ventricles (hollow spaces) in the brain. Also called CSF.

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.

Cerubidine  (seh-ROO-bih-dine)
A drug used to treat acute leukemias and some other types of cancer. It blocks a certain enzyme needed for cell division and DNA repair, and it may kill cancer cells. Cerubidine is a type of anthracycline antibiotic and a type of topoisomerase inhibitor. Also called daunomycin hydrochloride and daunorubicin hydrochloride.

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 (the 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 tests (a procedure in which cells are scraped from the cervix and looked at under a microscope).

cervical intraepithelial neoplasia grade 2/3  (SER-vih-kul IN-truh-eh-pih-THEE-lee-ul NEE-oh-play-zhuh …)
A condition in which abnormal cells grow on the thin layer of tissue that covers the cervix (the lower, narrow end of the uterus). These abnormal cells are not malignant (cancerous) but may become cancer. Cervical intraepithelial neoplasia grade 2/3 has features of CIN 2 and CIN 3. Also called CIN 2/3.

cervical intraepithelial neoplasia  (SER-vih-kul IN-truh-eh-pih-THEE-lee-ul NEE-oh-PLAY-zhuh)
Growth of abnormal cells on the surface of the cervix. Numbers from 1 to 3 may be used to describe how abnormal the cells are and how much of the cervical tissue is involved. Also called CIN.

cervical squamous intraepithelial neoplasia 1  (SER-vih-kul SKWAY-mus IN-truh-eh-pih-THEE-lee-ul NEE-oh-PLAY-zhuh ...)
A condition in which slightly abnormal cells grow on the thin layer of tissue that covers the cervix. These abnormal cells are not malignant (cancerous) but may become cancer. Also called CIN 1.

cervical squamous intraepithelial neoplasia 2  (SER-vih-kul SKWAY-mus IN-truh-eh-pih-THEE-lee-ul NEE-oh-PLAY-zhuh ...)
A condition in which moderately abnormal cells grow on the thin layer of tissue that covers the cervix. These abnormal cells are not malignant (cancerous) but may become cancer. Also called CIN 2.

cervical squamous intraepithelial neoplasia 3  (SER-vih-kul SKWAY-mus IN-truh-eh-pih-THEE-lee-ul NEE-oh-PLAY-zhuh …)
Abnormal cells are found in the cervical epithelium (the innermost lining of the cervix). These abnormal cells may become cancer and spread into nearby normal tissue. Also called CIN 3 and stage 0 cervical carcinoma in situ.

cervicectomy  (SER-vih-SEK-toh-mee)
Surgery to remove the cervix (the end of the uterus that forms a canal between the uterus and the vagina).The upper part of the vagina and certain pelvic lymph nodes may also be removed. Also called trachelectomy.

CerviPrep  (SER-vih-PREP)
A device used to deliver drugs directly to the cervix (the lower, narrow end of the uterus that forms a canal between the uterus and vagina). The CerviPrep covers the cervix and protects surrounding tissue. Drugs may be injected into the inner part of the cervix through a syringe attached to the device.

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 certain 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. Cetuximab binds to the epidermal growth factor receptor (EGFR), which is found on the surface of some types of 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-muh-mile)
A family of plants with daisy-like flowers. Two types are German chamomile and Roman or English chamomile. These are used in teas to calm and relax, to improve sleep, and to help with stomach problems. The essential oil (scented liquid taken from plants) of chamomile is used in perfumes, shampoos, lotions, and aromatherapy.

change of life  
The time of life when a woman no longer has menstrual periods. Change of life is reached when she hasn't had a period for 12 months in a row. Also called menopause.

Chantix  (CHAN-tix)
A drug used to help people stop smoking by acting the same way nicotine acts in the brain. It is a type of nicotine receptor partial agonist. Also called varenicline tartrate.

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.

charged-particle radiation therapy  (… PAR-tih-kul RAY-dee-AY-shun THAYR-uh-pee)
A type of external radiation therapy that uses a special machine to make invisible, high-energy particles (protons or helium ions) that kill cancer cells. This type of radiation may cause less damage to nearby healthy tissue than radiation therapy with high-energy x-rays.

chelating agent  (KEE-lay-ting AY-jent)
A chemical compound that binds tightly to metal ions. In medicine, chelating agents are used to remove toxic metals from the body. They are also being studied in the treatment of cancer.

chemical imbalance  (KEH-mih-kul im-BA-lunts)
Too much or too little of any substance that helps the body work the way it should. A chemical imbalance may be caused by certain tumors and can cause changes in behavior or emotion.

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  (KEE-moh-IH-myoo-noh-THAYR-uh-pee)
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 study  
In cancer prevention, a clinical trial that studies whether taking certain medicines, vitamins, minerals, or food supplements can prevent cancer. Also called agent study.

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  (KEE-moh-RAY-dee-oh-THAYR-uh-pee)
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.

chimeric  (ky-MEER-ik)
Having parts of different origins. In medicine, refers to a person, organ, or tissue that contains cells with different genes than the rest of the person, organ, or tissue. This may happen because of a mutation (genetic change) that occurs during development, or as a result of a transplant of cells, organs, or tissues from another person or from a different species. In the laboratory, a chimeric protein can be made by combining two different genes. For example, a chimeric antibody is made by joining antibody genes from two different species, such as human and mouse.

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  (chy-NEEZ ROO-barb)
The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. The scientific name is Rheum palmatum or Rheum officinale. Also called da-huang, Indian rhubarb, rhubarb, and Turkish rhubarb.

CHIR-265  
A substance being studied in the treatment of melanoma. CHIR-265 may block the growth of tumors and the growth of blood vessels from surrounding tissue to the tumor. It is a type of Raf kinase inhibitor and angiogenesis inhibitor.

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  (KLOR-oh-kwih-NOK-sah-leen sul-FAH-nuh-MIDE)
A substance being studied in the treatment of cancer. It is a type of topoisomerase inhibitor. Also called CQS.

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 the body needs in small amounts to function and stay healthy. Cholecalciferol helps the body use calcium and phosphorus to make strong bones and teeth. It is fat-soluble (can dissolve in fats and oils) and is found in fatty fish, egg yolks, and dairy products. Skin exposed to sunshine can also make cholecalciferol. Not enough cholecalciferol can cause a bone disease called rickets. It 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.

choline  (KOH-leen)
A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Choline helps cells make membranes, make a neurotransmitter (a chemical that helps nerve cells communicate with other cells), and remove fat from the liver. It is found in whole milk, beef liver, eggs, soy foods, and peanuts. Choline is water-soluble (can dissolve in water) and must be taken in every day. Not enough choline can cause diseases of the heart and blood vessels and damage to the liver. A form of choline is being studied in the treatment of some types of cancer and to reduce pain and fever. Choline is also being studied together with vitamin B12 in the prevention and treatment of cancer.

choline magnesium trisalicylate  (KOH-leen mag-NEE-see-um TRY-suh-LIH-sih-LAYT)
A substance used to treat arthritis and relieve pain, inflammation, and fever. It is also being studied in the treatment of acute myeloid leukemia (AML). Choline magnesium trisalicylate blocks the action of a substance that sends a pain message to the brain. It is a type of nonsteroidal anti-inflammatory drug (NSAID). Also called Trilisate.

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

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

chondrosarcoma  (KON-droh-sar-KOH-muh)
A type of cancer that forms in bone cartilage. It usually starts in the pelvis (between the hip bones), the shoulder, the ribs, or at the ends of the long bones of the arms and legs. A rare type of chondrosarcoma called extraskeletal chondrosarcoma does not form in bone cartilage. Instead, it forms in the soft tissues of the upper part of the arms and legs. Chondrosarcoma can occur at any age but is more common in people older than 40 years. It is a type of bone cancer.

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

chorioadenoma destruens  (KOR-ee-oh-A-deh-NOH-muh des-TROO-ens)
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 hens' eggs that helps chicken embryos get enough oxygen and calcium for development. The calcium comes from the egg shell.

chorioblastoma  (KOR-ee-oh-blas-TOH-muh)
A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all chorioblastomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Chorioblastomas spread through the blood to other organs, especially the lungs. They are a type of gestational trophoblastic disease. Also called choriocarcinoma, chorioepithelioma, and chorionic carcinoma.

choriocarcinoma  (KOR-ee-oh-KAR-sih-NOH-muh)
A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all choriocarcinomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Choriocarcinomas spread through the blood to other organs, especially the lungs. They are a type of gestational trophoblastic disease. Also called chorioblastoma, chorioepithelioma, and chorionic carcinoma.

chorioepithelioma  (KOR-ee-oh-EH-pih-THEE-lee-OH-muh)
A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all chorioepitheliomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Chorioepitheliomas spread through the blood to other organs, especially the lungs. They are a type of gestational trophoblastic disease. Also called chorioblastoma, choriocarcinoma, and chorionic carcinoma.

chorionic carcinoma  (KOR-ee-AH-nik KAR-sih-NOH-muh)
A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all chorionic carcinomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Chorionic carcinomas spread through the blood to other organs, especially the lungs. They are a type of gestational trophoblastic disease. Also called chorioblastoma, choriocarcinoma, and chorioepithelioma.

choroid  (KOR-oid)
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white outer layer of the eye) and the retina (the inner layer of nerve tissue at the back of the eye). The choriod is filled with blood vessels that bring oxygen and nutrients to the eye.

choroid plexus tumor  (KOR-oyd PLEK-sus TOO-mer)
A rare type of cancer that occurs in the ventricles of the brain. It usually occurs in children younger than 2 years.

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. Also called continuous hyperthermic peritoneal perfusion.

chromaffin cell  (KROH-muh-fin ...)
A type of cell that makes neurohormones (chemicals that are made by nerve cells and used to send signals to other cells) and releases them into the blood. Chromaffin cells make epinephrine (adrenaline) and norepinephrine (noradrenaline). They are found in the adrenal glands or in groups of nerve cells called ganglia.

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

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

chronic eosinophilic leukemia  (KRAH-nik EE-oh-SIH-noh-FIH-lik loo-KEE-mee-uh)
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  (KRAH-nik GRAN-yoo-loh-SIH-tik loo-KEE-mee-uh)
A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myelogenous leukemia, chronic myeloid leukemia, and CML.

chronic idiopathic myelofibrosis  (KRAH-nik IH-dee-oh-PA-thik MY-eh-loh-fy-BROH-sis)
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, idiopathic myelofibrosis, myelosclerosis with myeloid metaplasia, and primary myelofibrosis.

chronic leukemia  (KRAH-nik loo-KEE-mee-uh)
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  (KRAH-nik LIM-foh-BLAS-tik loo-KEE-mee-uh)
A slow-growing type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are found in the blood and bone marrow. Also called chronic lymphocytic leukemia and CLL.

chronic lymphocytic leukemia  (KRAH-nik LIM-foh-SIH-tik loo-KEE-mee-uh)
A slow-growing type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are found in the blood and bone marrow. Also called chronic lymphoblastic leukemia and CLL.

chronic myelogenous leukemia  (KRAH-nik MY-eh-LAH-jeh-nus loo-KEE-mee-uh)
A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic granulocytic leukemia, chronic myeloid leukemia, and CML.

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

chronic myelomonocytic leukemia  (KRAH-nik MY-eh-loh-MAH-noh-SIH-tik loo-KEE-mee-uh)
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. Also called CMML.

chronic neutrophilic leukemia  (KRAH-nik NOO-tro-FIH-lik loo-KEE-mee-uh)
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 obstructive pulmonary disease  (KRAH-nik ob-STRUK-tiv PUL-muh-NAYR-ee dih-ZEEZ)
A type of lung disease marked by permanent damage to tissues in the lungs, making it hard to breathe. Chronic obstructive pulmonary disease includes chronic bronchitis, in which the bronchi (large air passages) are inflamed and scarred, and emphysema, in which the alveoli (tiny air sacs) are damaged. It develops over many years and is usually caused by cigarette smoking. Also called COPD.

chronic pain  (KRAH-nik payn)
Pain that can range from mild to severe, and persists or progresses over a long period of time.

chronic phase  (KRAH-nik fayz)
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  (KRAH-nik FAYZ KRAH-nik MY-eh-LAH-jeh-nus loo-KEE-mee-uh)
A phase of chronic myelogenous leukemia in which fewer than 10% 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 being studied in the treatment of some types of cancer. CI-1033 blocks the action of proteins called epidermal growth factor receptors, and may cause cancer cells to die. It is a type of tyrosine kinase inhibitor. Also called canertinib and canertinib dihydrochloride.

CI-958  
A substance being studied in the treatment of some types of cancer. CI-958 binds to DNA and stops cells, including cancer cells, from repairing damage to DNA and from making more DNA, RNA, and protein. It is a type of DNA intercalator. 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 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.

ciliary body  (SIH-lee-ayr-ee ...)
A part of the middle layer of the wall of the eye. The ciliary body includes the ring-shaped muscle that changes the size of the pupil and the shape of the lens when the eye focuses. It also makes the fluid that fills the eye.

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

CIN  
Growth of abnormal cells on the surface of the cervix. Numbers from 1 to 3 may be used to describe how abnormal the cells are and how much of the cervical tissue is involved. Also called cervical intraepithelial neoplasia.

CIN 1  
A condition in which slightly abnormal cells grow on the thin layer of tissue that covers the cervix. These abnormal cells are not malignant (cancerous) but may become cancer. Also called cervical squamous intraepithelial neoplasia 1.

CIN 2  
A condition in which moderately abnormal cells grow on the thin layer of tissue that covers the cervix. These abnormal cells are not malignant (cancerous) but may become cancer. Also called cervical squamous intraepithelial neoplasia 2.

CIN 2/3  
A condition in which abnormal cells grow on the thin layer of tissue that covers the cervix (the lower, narrow end of the uterus). These abnormal cells are not malignant (cancerous) but may become cancer. CIN 2/3 has features of CIN 2 and CIN 3. Also called cervical intraepithelial neoplasia grade 2/3.

CIN 3  
Abnormal cells are found in the cervical epithelium (the innermost lining of the cervix). These abnormal cells may become cancer and spread into nearby normal tissue. Also called cervical squamous intraepithelial neoplasia 3 and stage 0 cervical carcinoma in situ.

Cipro  
A drug that is used to treat infections caused by bacteria and is being studied in the treatment of bladder cancer. Cipro is a type of fluoroquinolone. Also called ciprofloxacin.

ciprofloxacin  (sip-roe-FLOX-a-sin)
A drug that is used to treat infections caused by bacteria and is being studied in the treatment of bladder cancer. Ciprofloxacin is a type of fluoroquinolone. Also called Cipro.

circulation  (ser-kyoo-LAY-shun)
In the body, the flow of blood through the heart and blood vessels, and the flow of lymph through the lymph vessels.

circulatory system  (SER-kyoo-lah-tor-ee SIS-tem)
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  
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. Also called Cancer Information Service.

cisplatin  (sis-PLA-tin)
A drug used to treat many types of cancer. Cisplatin contains the metal platinum. It kills cancer cells by damaging their DNA and stopping them from dividing. Cisplatin is a type of alkylating agent.

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  (SIH-trik A-sid/poh-TAH-see-um-SOH-dee-um SIH-trayt)
A drug used in the treatment of metabolic acidosis (a disorder in which the blood is too acidic).

Citrovorum factor  (sih-troh-VOR-um FAK-ter)
The active ingredient in a drug used to reduce the toxic effects of folic acid antagonists (substances that block the action of folic acid), especially the anticancer drug methotrexate. It is also used to treat anemia and it is used with fluorouracil to treat symptoms of advanced colorectal cancer. It is also being studied in the treatment of other types of cancer and other conditions. Citrovorum factor is a form of folic acid, a B-complex vitamin that the body needs to make red blood cells and to function and stay healthy. Citrovorum factor is a type of chemoprotective agent and a type of chemosensitizing agent. Also called folinic acid and leucovorin.

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.

classical Hodgkin lymphoma  (KLA-sih-kul HOJ-kin lim-FOH-muh)
The most common type of Hodgkin lymphoma, which is a cancer of the immune system. Classical Hodgkin lymphoma is marked by the presence of a type of cell called the Reed-Sternberg cell.

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  (kleer sel)
A type of cell that looks clear inside when viewed under a microscope.

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

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

clear cell sarcoma of the kidney  (kleer sel sar-KOH-muh ...KID-nee)
A rare type of kidney cancer, in which the inside of the cells look clear when viewed under a microscope. 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  
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 researcher  (KLIH-nih-kul reh-SER-cher)
A health professional who works directly with patients, or uses data from patients, to do research on health and disease and to develop new treatments. Clinical researchers may also do research on how health care practices affect health and disease.

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 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 clinical study.

clinician  (klih-NIH-shun)
A health professional who takes care of patients.

CLL  
A slow-growing type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are found in the blood and bone marrow. Also called chronic lymphoblastic leukemia and chronic lymphocytic leukemia.

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  (kloh-FAYR-uh-been)
A drug used to treat certain types of acute lymphoblastic leukemia in children. It is also being studied in the treatment of other types of cancer. Clofarabine is a type of nucleoside analog. Also called Clolar.

Clolar  (KLOH-lar)
A drug used to treat certain types of acute lymphoblastic leukemia in children. It is also being studied in the treatment of other types of cancer. Clolar is a type of nucleoside analog. Also called clofarabine.

clonidine  (KLOH-nih-deen)
The active ingredient in a drug used to treat high blood pressure. It is also being studied in the treatment of certain types of cancer pain. It blocks the release of chemicals from nerve endings that make blood vessels constrict (get narrower). Clonidine is a type of antihypertensive agent and a type of alpha-adrenergic agonist.

clonidine hydrochloride  (KLOH-nih-deen HY-droh-KLOR-ide)
A drug used to treat high blood pressure. It is also being studied in the treatment of certain types of cancer pain. It blocks the release of chemicals from nerve endings that make blood vessels constrict (get narrower). Clonidine hydrochloride is a type of antihypertensive agent and a type of alpha-adrenergic agonist. Also called Catapres.

Clostridium difficile  (klah-STRIH-dee-um dih-FIS-ih-lee)
A type of bacterium found in human and animal waste. Clostridium difficile is a common cause of diarrhea that occurs in hospitals. It can also cause diarrhea or other intestinal disorders in patients treated with antibiotics.

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

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. Also called cytomegalovirus.

cnicin  (NIH-sin)
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 is a type of sesquiterpene lactone.

CNS  
The brain and spinal cord. Also called central nervous system.

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

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

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

CNS sanctuary therapy  (...SANK-choo-wayr-ee THAYR-uh-pee)
Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It kills cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called central nervous system prophylaxis, central nervous system sanctuary therapy, and CNS prophylaxis.

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

CNTO 328  
A chimeric (made from human and mouse proteins) monoclonal antibody being studied in the treatment of advanced kidney cancer and other types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. CNTO 328 works by blocking inflammation and tumor growth. Also called anti-IL-6 chimeric monoclonal antibody and cCLB8.

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-BA-luh-min)
A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Cobalamin helps make red blood cells, DNA, RNA, energy, and tissues, and keeps nerve cells healthy. It is found in liver, meat, eggs, poultry, shellfish, milk, and milk products. Cobalamin is water-soluble (can dissolve in water) and must be taken in every day. Not enough cobalamin can cause certain types of anemia (a condition in which the number of red blood cells is below normal) and neurologic disorders. It is being studied with folate in the prevention and treatment of some types of cancer. Also called cyanocobalamin and 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 tailbone.

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

codeine  (KOH-deen)
A drug made from opium or morphine that is used to relieve pain and to prevent coughing and diarrhea. Codeine is a type of opiate. Also called codeine phosphate.

codeine phosphate  (KOH-deen FOS-fayt)
A drug made from opium or morphine that is used to relieve pain and to prevent coughing and diarrhea. Codeine phosphate is a type of opiate. Also called codeine.

coenzyme Q10  
A nutrient that the body needs in small amounts to function and stay healthy. Coenzyme Q10 helps mitochondria (small structures in the cell) make energy. It is an antioxidant that helps prevent cell damage caused by free radicals (highly reactive chemicals). Coenzyme Q10 is fat-soluble (can dissolve in fats and oils) and is found in fatty fish, beef, soybeans, peanuts, and spinach. It is being studied in the prevention and treatment of some types of cancer and heart disease and in the relief of side effects caused by some cancer treatments. Also called CoQ10, Q10, ubiquinone, and vitamin Q10.

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.

cognition  (kog-NIH-shun)
The mental process of thinking, learning, remembering, being aware of surroundings, and using judgment.

cohort  (koh-HORT)
A group of individuals who share a common trait, such as birth year. In medicine, a cohort is a group that is part of a clinical trial or study and is observed over a period of time.

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 being studied in the treatment of cancer. COL-3 may block tumor growth by preventing the growth of new blood vessels needed for tumors to grow. It is a type of matrix metalloproteinase inhibitor and a type of angiogenesis inhibitor.

COL18A1  
A substance being studied in the treatment of cancer. COL18A1 is made from a type of collagen (a protein found in cartilage and other connective tissue). It may prevent the growth of new blood vessels needed for tumors to grow. COL18A1 is a type of angiogenesis inhibitor. Also called endostatin.

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  (koh-LEK-toh-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.

colloidal gold-bound tumor necrosis factor  (...TOO-mer neh-KROH-sis FAK-ter)
A substance being studied in the treatment of some types of cancer. Colloidal gold-bound tumor necrosis factor is made in the laboratory by binding a cancer-killing protein called tumor necrosis factor (TNF) to the surface of very tiny particles of gold. These TNF-gold particles may kill cancer cells without harming healthy tissue. Also called Aurimmune and TNF-bound colloidal gold.

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  (KOH-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  (KOH-lun KAN-ser)
Cancer that forms in the tissues of the colon (the longest part of the large intestine). Most colon cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids).

colon crypt  (KOH-lun KRIPT)
Tube-like gland found in the lining of the colon and rectum. Colon crypt cells renew the lining of the intestine and make mucus. Also called gland of Lieberkuhn.

colon polyp  (KOH-lun PAH-lip)
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-NOS-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  (KAH-luh-nee-STIM-yoo-LAY-ting FAK-ter)
A substance that stimulates the production of blood cells. Colony-stimulating factors include granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and promegapoietin.

colorectal  (KOH-loh-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 (the longest part of the large intestine) and/or the rectum (the last several inches of the large intestine before the anus).

colostomy  (koh-LOS-toh-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.

coma  (KOH-muh)
A condition in which a patient is in a state of deep sleep and cannot be awakened. A coma may be caused by many things, including trauma, drugs, toxins, or certain diseases.

combination chemotherapy  (KOM-bih-NAY-shun KEE-moh-THAYR-uh-pee)
Treatment using more than one anticancer drug.

combretastatin A4 phosphate  (kum-BREE-tuh-STA-tin … FOS-fayt)
A substance being studied in the treatment of cancer. It decreases the flow of blood to tumors and may kill cancer cells. Combretastatin A4 phosphate comes from the African bush willow. It is a type of tubulin-binding agent and a type of vascular targeting agent.

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 a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called palliative care, supportive care, and symptom management.

common bile duct  
A tube or vessel in the body that carries bile from the liver and gallbladder into the duodenum (the upper part of the small intestine).

comorbidity  
The condition of having two or more diseases at the same time.

comparative anatomy  (kum-PAYR-uh-tiv uh-NA-toh-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 trials allow patients 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 infections and other diseases.

complementary and alternative medicine  (KOM-pleh-MEN- tuh-ree... all-TER-nuh-tiv MEH-dih-sin)
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. Also called CAM.

complementary medicine  (KOM-pleh-MEN-tuh-ree MEH-dih-sin)
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  
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 and CBC.

complete hysterectomy  (kum-PLEET HIS-teh-REK-toh-mee)
Surgery to remove the entire uterus, including the cervix. Also called total hysterectomy.

complete metastasectomy  (... meh-TAS-tuh-SEK-toh-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 complete response.

complete response  (kum-PLEET reh-SPONTS)
The disappearance of all signs of cancer in response to treatment. This does not always mean the cancer has been cured. Also called complete remission.

compliance  (kum-PLY-ants)
The act of following a medical regimen or schedule correctly and consistently, including taking medicines or 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.

compression pump  (kum-PREH-shun …)
A machine used to keep blood and lymph flowing by pushing air through bands or sleeves that are placed on the arms or legs.

compulsion  (kum-PUL-zhun)
An uncontrollable urge to say or do something without an obvious reason. A person may repeat a behavior, such as hand-washing, over and over.

computed tomographic colonography  (kum-PYOO-ted toh-muh-GRA-fik KOH-lun-AH-gruh-fee)
A procedure in which a detailed picture of the colon is created by an x-ray machine linked to a computer. Also called CTC.

computed tomography colography  (kum-PYOO-ted toh-MAH-gruh-fee koh-LAH-gruh-fee)
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.

computed tomography scan  (kum-PYOO-ted toh-MAH-gruh-fee skan)
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, computerized axial tomography scan, computerized tomography, and CT scan.

computerized axial tomography scan  (kum-PYOO-teh-RIZED AK-see-ul toh-MAH-gruh-fee skan)
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 scan, computerized tomography, and CT scan.

computerized tomography  (kum-PYOO-teh-RIZED toh-MAH-gruh-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 scan, computerized axial tomography scan, and CT scan.

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

concurrent therapy  (kun-KER-ent THAYR-uh-pee)
A treatment that is given at the same time as another.

conditioned response  (kun-DIH-shund reh-SPONTS)
A type of learning in which repeated exposure to something may affect a person’s behavior when they encounter an unrelated object, sound, or smell that occurred at the same time as the initial exposure. For example, a patient who always feels sick after receiving chemotherapy in a clinic that smells a certain way may be conditioned to feel sick when smelling the same odor in a different place.

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.

conditioning regimen  (con-DIH-shuh-ning REH-jih-men)
The treatments used to prepare a patient for stem cell transplantation (a procedure in which a person receives blood stem cells, which make any type of blood cell). A conditioning regimen may include chemotherapy, monoclonal antibody therapy, and radiation to the entire body. It helps make room in the patient’s bone marrow for new blood stem cells to grow, helps prevent the patient's body from rejecting the transplanted cells, and helps kill any cancer cells that are in the body.

condyloma  (KON-dih-LOH-muh)
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. Also called 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.

congenital mesoblastic nephroma  (con-JEH-nih-tul mez-oh-BLAS-tik neh-FROH-muh)
A type of kidney tumor that is usually found before birth by ultrasound or within the first 3 months of life. It contains fibroblastic cells (connective tissue cells), and may spread to the other kidney or to nearby tissue. Congenital mesoblastic nephroma is more common in males.

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  (kun-SAH-lih-DAY-shun THAYR-uh-pee)
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  (kon-TIN-yoo-us HY-per-THER-mik PAYR-ih-toh-NEE-ul per-FYOO-zhun)
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. Also called CHPP.

continuous infusion  (kon-TIN-yoo-us in-FYOO-zhun)
The administration of a fluid into a blood vessel, usually over a prolonged period of time.

continuum of care  (kon-TIN-yoo-um …)
In medicine, describes the delivery of health care over a period of time. In patients with a disease, this covers all phases of illness from diagnosis to the end of life.

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

conventional medicine  (kun-VEN-shuh-nul MEH-dih-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 allopathic medicine, biomedicine, mainstream medicine, orthodox medicine, and Western 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.

Coomb's test  
A laboratory test to identify antibodies that can bind to the surface of red blood cells or platelets and destroy them. This test is used to diagnose certain blood disorders in which patients make antibodies to their own red blood cells or platelets. It is also used to determine blood type. Also called antiglobulin test.

COPD  
A type of lung disease marked by permanent damage to tissues in the lungs, making it hard to breathe. COPD includes chronic bronchitis, in which the bronchi (large air passages) are inflamed and scarred, and emphysema, in which the alveoli (tiny air sacs) are damaged. It develops over many years and is usually caused by cigarette smoking. Also called chronic obstructive pulmonary disease.

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.

copolymer  (KOH-pah-lih-mer)
A molecule made up of two or more different kinds of small molecules called monomers. The monomers are joined together in a repeating pattern.

CoQ10  
A nutrient that the body needs in small amounts to function and stay healthy. CoQ10 helps mitochondria (small structures in the cell) make energy. It is an antioxidant that helps prevent cell damage caused by free radicals (highly reactive chemicals). CoQ10 is fat-soluble (can dissolve in fats and oils) and is found in fatty fish, beef, soybeans, peanuts, and spinach. It is being studied in the prevention and treatment of some types of cancer and heart disease and in the relief of side effects caused by some cancer treatments. Also called coenzyme Q10, Q10, ubiquinone, and vitamin Q10.

cordectomy  (kor-DEK-toh-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  (... BY-op-see)
The removal of a tissue sample with a wide 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 bypass  (KOR-uh-NAYR-ee AR-tuh-ree BY-pas)
Surgery in which a healthy blood vessel taken from another part of the body is used to make a new path for blood around a blocked artery leading to the heart. This restores the flow of oxygen and nutrients to the heart. Also called aortocoronary bypass and CAB.

coronary artery disease  (KOR-uh-NAYR-ee AR-tuh-ree 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 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 CAD and 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 CAD and coronary artery disease.

corpus  
The body of the uterus.

corticosteroid  (KOR-tih-koh-STAYR-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 hormone made in the pituitary gland. Corticotropin acts on the outer part of the adrenal gland to control its release of corticosteroid hormones. More corticotropin is made during times of stress. Also called ACTH and adrenocorticotropic hormone.

cortisol  (KOR-tih-sol)
A hormone made by the adrenal cortex (the outer layer of the adrenal gland). It helps the body use glucose (a sugar), protein, and fats. Cortisol made in the laboratory is called hydrocortisone. It is used to treat many conditions, including inflammation, allergies, and some cancers. Cortisol is a type of glucocorticoid hormone.

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  (kah-RY-nee-bak-TEER-ee-um GRAN-yoo-LOH-sum)
A bacterium that may stimulate the immune system to fight cancer.

coumarin  (KOO-muh-rin)
A substance used to make drugs that prevent and treat blood clots in blood vessels and treat certain heart conditions. Coumarin is taken from certain plants and can also be made in the laboratory. It is a type of anticoagulant.

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 cyclo-oxygenase inhibitor.

COX-2  
An enzyme that speeds up the formation of substances that cause inflammation and pain. It may also cause tumor cells to grow. Some tumors have high levels of COX-2 and blocking its activity may reduce tumor growth. Also called cyclooxygenase-2 and prostaglandin-endoperoxide synthase 2.

COX-2 inhibitor  (kox...in-HIH-bih-ter)
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. Also called cyclo-oxygenase-2 inhibitor.

Cozaar  (KOH-zahr)
A drug used to treat high blood pressure. Cozaar blocks the action of chemicals that make blood vessels constrict (get narrower). It is a type of angiotensin II receptor antagonist. Also called losartan and losartan potassium.

CP-358,774  
A drug used to treat certain types of non-small cell lung cancer. It is also used together with gemcitabine to treat pancreatic cancer and is being studied in the treatment of other types of cancer. CP-358,774 is a type of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. Also called erlotinib, erlotinib hydrochloride, OSI-774, and Tarceva.

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 some types of cancer. It belongs to the family of drugs called biological response modifiers. Also called PF-3512676 and ProMune.

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

CQS  
A substance being studied in the treatment of cancer. It is a type of topoisomerase inhibitor. Also called chloroquinoxaline sulfonamide.

cramp  
A sharp pain that occurs when a muscle suddenly contracts (tightens up). Cramps commonly occur in the abdomen and legs.

craniopharyngioma  (KRAY-nee-oh-fuh-RIN-jee-OH-muh)
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-toh-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 SIDS and sudden infant death syndrome.

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-ter-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 126–F, Cancell, Cantron, Jim’s Juice, JS–101, JS–114, Protocel, and Sheridan’s Formula.

Crohn disease  (KRONE dih-ZEEZ)
Chronic inflammation of the gastrointestinal tract, most commonly the small intestine and colon. Crohn disease increases the risk for colorectal cancer and small intestine cancer. Also called regional enteritis.

cruciferous vegetable  (KROO-sih-feh-rus VEJ-tuh-bul)
A member of the family of vegetables that includes broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, kale, and turnips. These vegetables contain substances that may protect against cancer. Also called Brassica vegetable.

cryoablation  (KRY-oh-uh-BLAY-shun)
A procedure in which tissue is frozen to destroy abnormal cells. This is usually done with a special instrument that contains liquid nitrogen or liquid carbon dioxide. Also called cryosurgery.

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-oh-SER-juh-ree)
A procedure in which tissue is frozen to destroy abnormal cells. This is usually done with a special instrument that contains liquid nitrogen or liquid carbon dioxide. Also called cryoablation.

cryotherapy  (KRY-oh-THAYR-uh-pee)
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  
The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin layers of tissue that cover and protect the brain and spinal cord). CSF is made by tissue called the choroid plexus in the ventricles (hollow spaces) in the brain. Also called cerebrospinal fluid.

CSP  
A type of tumor found in breast or prostate tissue. It is often large and bulky and grows quickly. It may be benign (not cancer) or malignant (cancer) and may spread to other parts of the body. Also called cystosarcoma phyllodes and phyllodes tumor.

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 CAT scan, computed tomography scan, computerized axial tomography scan, and computerized tomography.

CT-2103  
A form of the anticancer drug paclitaxel combined with a protein called poliglumex that may have fewer side effects and work better than paclitaxel. It is being studied in the treatment of breast cancer, ovarian cancer, lung cancer, and other types of cancer. It belongs to the family of drugs called mitotic inhibitors. Also called paclitaxel poliglumex, paclitaxel polyglutamate, and Xyotax.

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 is a type of DNA topoisomerase inhibitor. 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.

CT-322  
A substance being studied in the treatment of cancer. CT-322 prevents the growth of new blood vessels needed for tumors to grow and may kill cancer cells. It is a type of vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor and a type of angiogenesis inhibitor. Also called Angiocept and VEGFR-2 inhibitor CT-322.

CT53518  
A substance being studied in the treatment of some types of cancer. It may stop cancer cell growth by blocking certain enzymes and by preventing the growth of new blood vessels needed for tumors to grow. It is a type of tyrosine kinase inhibitor. Also called MLN518 and tandutinib.

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 tomographic colonography.

Cubicin  (KYOO-bih-sin)
A drug used to treat certain bacterial skin and bloodstream infections in adults. Cubicin is also being studied in the treatment of fever and neutropenia (an abnormal decrease in the number of neutrophils, a type of white blood cell) in patients with cancer. It is a type of antibiotic. Also called daptomycin.

culture  (KUL-chur)
The beliefs, values, and behaviors that are shared within a group, such as a religious group or a nation. Culture includes language, customs, and beliefs about roles and relationships.

cultured cell  
A human, plant, or animal cell that has been adapted to grow in the laboratory. Cultured cells may be used to diagnose infections, to test new drugs, and in research.

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.

CUP  
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. Also called cancer of unknown primary origin and carcinoma of unknown primary.

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.

Cushing disease  (KUSH-ing dih-ZEEZ)
A condition in which there is too much cortisol (a hormone made by the outer layer of the adrenal gland) in the body. In Cushing disease, this happens when an adenoma (benign tumor) in the pituitary gland makes too much adrenocorticotropic hormone (ACTH). This causes the adrenal gland to make too much cortisol. Symptoms include a round face, thin arms and legs, severe fatigue and muscle weakness, high blood pressure and high blood sugar, purple or pink stretch marks on the skin, and weight gain, especially in the abdomen.

Cushing syndrome  (KUSH-ing SIN-drome)
A condition in which there is too much cortisol (a hormone made by the outer layer of the adrenal gland) in the body. Cushing syndrome may be caused by taking too many steroid drugs or by certain types of tumors. Tumors that make adrenocorticotropic hormone (ACTH) cause the adrenal gland to make too much cortisol. Symptoms of Cushing syndrome include a round face, thin arms and legs, severe fatigue and muscle weakness, high blood pressure, high blood sugar, purple or pink stretch marks on the skin, and weight gain, especially in the abdomen.

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  (kyoo-TAY-nee-us … lim-FOH-muh)
Any of a group of T-cell non-Hodgkin lymphomas that begins in the skin as an itchy, red rash that can thicken or form a tumor. The most common types are mycosis fungoides and Sézary syndrome.

cyanocobalamin  (SY-uh-NOH-koh-BA-luh-min)
A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Cyanocobalamin helps make red blood cells, DNA, RNA, energy, and tissues, and keeps nerve cells healthy. It is found in liver, meat, eggs, poultry, shellfish, milk, and milk products. Cyanocobalamin is water-soluble (can dissolve in water) and must be taken in every day. Not enough cyanocobalamin can cause certain types of anemia (a condition in which the number of red blood cells is below normal) and neurologic disorders. It is being studied with folate in the prevention and treatment of some types of cancer. Also called cobalamin and vitamin B12.

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

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

CYC116  
A substance being studied in the treatment of some types of cancer. It blocks certain enzymes involved in cell division and may kill cancer cells. It may also prevent the growth of new blood vessels needed for tumors to grow It is a type of protein kinase inhibitor.

cyclo-oxygenase inhibitor  (SY-kloh-OK-sih-jeh-NASE in-HIH-bih-ter)
COX inhibitor. A type of drug that is used to treat inflammation and pain, and is being studied in the prevention and treatment of cancer. Cyclo-oxygenase inhibitors belong to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Also called COX inhibitor.

cyclo-oxygenase-2 inhibitor  (SY-kloh-OK-sih-jeh-NASE in-HIH-bih-ter)
A nonsteroidal anti-inflammatory drug used to relieve pain and inflammation. Cyclo-oxygenase-2 inhibitors are being studied in the prevention of colon polyps, and as anticancer drugs. Also called COX-2 inhibitor.

cyclooxygenase-2  (SY-kloh-OK-sih-jeh-NAYZ …)
An enzyme that speeds up the formation of substances that cause inflammation and pain. It may also cause tumor cells to grow. Some tumors have high levels of cyclooxygenase-2 and blocking its activity may reduce tumor growth. Also called COX-2 and prostaglandin-endoperoxide synthase 2.

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.

Cymbalta  (sim-BAL-tuh)
A drug used to treat depression and peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) that can occur with diabetes. It is also being studied in the treatment of peripheral neuropathy caused by certain anticancer drugs. Cymbalta increases the amount of certain chemicals in the brain that help relieve depression and pain. It is a type of serotonin and norepinephrine reuptake inhibitor. Also called duloxetine and duloxetine hydrochloride.

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-toh-mee)
Surgery to remove all or part of the bladder (the organ that holds urine) or to remove a cyst (a sac or capsule in the body).

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) and the prostate. In a radical cystoprostatectomy, the seminal vesicles are also removed. The prostate and seminal vesicles are glands in the male reproductive system that help make semen. Also called prostatocystectomy.

cystosarcoma phyllodes  (SIS-toh-sar-KOH-muh fih-LOH-deez)
A type of tumor found in breast or prostate tissue. It is often large and bulky and grows quickly. It may be benign (not cancer) or malignant (cancer) and may spread to other parts of the body. Also called CSP and 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-yoo-ree-THREK-toh-mee)
Surgery to remove the bladder (the organ that holds urine) and urethra (the tube through which urine leaves the body).

cytarabine  (sy-TAYR-uh-been)
A drug used to treat certain types of leukemia and prevent the spread of leukemia to the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). It is also being studied in the treatment of other types of cancer. Cytarabine blocks tumor growth by stopping DNA synthesis. It is a type of antimetabolite.

cytarabine liposome  (sy-TAYR-uh-been LY-poh-SOME)
A form of the anticancer drug cytarabine that is contained inside very tiny, fat-like particles. It may have fewer side effects and work better than cytarabine. It is used to treat lymphoma that has spread to the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). It is also being studied in the treatment of other types of cancer. It is a type of antimetabolite. Also called Depo-Cyt and liposomal cytarabine.

cytochlor  (SY-toh-klor)
A substance being studied in the treatment of cancer. It is a type of radiosensitizer.

cytochrome P450 enzyme system  (SY-tuh-krome ... EN-zym SIS-tem)
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  (SY-toh-jeh-NEH-tix)
The study of chromosomes and chromosomal abnormalities.

cytokine  (SY-toh-kine)
A substance that is made by cells of the immune system. Some cytokines can boost the immune response and others can suppress it. Cytokines can also be made in the laboratory by recombinant DNA technology and used in the treatment of various diseases, including cancer.

cytology  (sy-TAH-loh-jee)
The study of cells using a microscope.

cytomegalovirus  (SY-tuh-meh-guh-loh-VY-rus)
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. Also called CMV.

Cytomel  (SY-toh-mel)
A drug that is used to treat certain thyroid (a gland located near the voice box) conditions. It is also being studied in the treatment of thyroid cancer. Cytomel is made in the laboratory and is a form of the thyroid hormone triiodthyronine (T3). Also called liothyronine sodium and Triostat.

cytopenia  (SY-toh-PEE-nee-uh)
A condition in which there is a lower-than-normal number of blood cells.

cytoplasm  (SY-toh-PLA-zum)
The fluid inside a cell but outside the cell's nucleus. Most chemical reactions in a cell take place in the cytoplasm.

cytotoxic  (SY-toh-TOK-sik)
Cell-killing.

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

cytotoxic T cell  (SY-toh-TOK-sik ... sel)
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.

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