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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Cancer Information Service CIS. The Cancer Information Service is the National Cancer Institute’s (NCI) link to the public, interpreting and explaining research findings in a clear, understandable manner and providing personalized answers to questions about cancer. Talk with CIS staff toll-free by calling 1-800-4-CANCER (1-800-422-6237), or reach them online through LiveHelp, NCI’s instant messaging service, at http://cancer.gov.

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

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

cancer vaccine A vaccine designed to prevent or treat cancer.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

cardiac Having to do with the heart.

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

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

cardiopulmonary Having to do with the heart and lungs.

cardiotoxicity Toxicity that affects the heart.

cardiovascular Having to do with the heart and blood vessels.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

cell motility The ability of a cell to move.

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

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

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

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

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

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

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

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

centimeter A measure of length in the metric system. A centimeter is one hundredth of a meter. There are 2½ centimeters in an inch.

central nervous system CNS. The brain and spinal cord.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

cetuximab A type of monoclonal antibody being studied in the diagnosis and treatment of cancer. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

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 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.

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.

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

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

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

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

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

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

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

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

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

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

chemotherapeutic agent A drug used to treat cancer.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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