Abdomen (AB-do-men): The part of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.
Accelerated phase (ak-SEL-er-ay-ted): Refers to chronic myelogenous leukemia that is progressing. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than in the chronic phase, but not as high as in the blast phase.
Achlorhydria (a-klor-HY-dree-a): A lack of hydrochloric acid in the digestive juices in the stomach. Hydrochloric acid helps digest food.
Acoustic (ah-KOOS-tik): Related to sound or hearing.
Actinic keratosis (ak-TIN-ik ker-a-TO-sis): A precancerous condition of thick, scaly patches of skin; also called solar or senile keratosis.
Acute leukemia: Leukemia that progresses rapidly.
Adenocarcinoma (AD-in-o-kar-sin-O-ma): Cancer that begins in cells that line certain internal organs.
Adenoma (AD-in-o-ma): A noncancerous tumor.
Adjuvant therapy (AD-joo-vant): Treatment given in addition to the primary treatment to enhance the effectiveness of the primary treatment.
Adrenal glands (a-DREE-nal): A pair of small glands, one located on top of each kidney. The adrenal glands produce hormones that help control heart rate, blood pressure, the way the body uses food, and other vital functions.
Aflatoxin (AF-la-TOK-sin): A substance made by a mold that is often found on poorly stored grains and nuts. Aflatoxins are known to cause cancer in animals.
Agranulocyte (A-gran-yoo-lo-SITE): A type of white blood cell; monocytes and lymphocytes are agranulocytes.
Allogeneic bone marrow transplantation (AL-o-jen-AY-ik): A procedure in which a patient receives bone marrow from a compatible, though not genetically identical, donor.
Allogeneic transplant: In this type of transplant, the blood or bone marrow cells to be transplanted come from a matched or unmatched donor.
Alpha-fetoprotein (AL-fa FEE-to-PRO-teen): A protein often found in abnormal amounts in the blood of patients with liver cancer.
Alveoli (al-VEE-o-lye): Tiny air sacs at the end of the bronchioles.
Amputation (am-pyoo-TAY-shun): Surgery to remove all or some of a body part.
Amylase (AM-il-aze): An enzyme that helps the body digest starches.
Anaplastic (an-ah-PLAS-tik): A term used to describe cancer cells that divide rapidly and bear little or no resemblance to normal cells.
Anastamosis (an-AS-ta-MO-sis): A procedure to connect healthy sections of the colon or rectum after the diseased portion has been surgically removed.
Androgen (AN-dro-jenz): A hormone that promotes the development and maintenance of male sex characteristics.
Anemia (a-NEE-mee-a): A decrease in the normal amounts of red blood cells.
Anesthesia (an-es-THEE-zha): Loss of feeling or awareness. A local anesthetic causes loss of feeling in a part of the body. A general anesthetic puts the person to sleep.
Anesthetic (an-es-THET-ik): A substance that causes loss of feeling or awareness. A local anesthetic causes loss of feeling in a part of the body. A general anesthetic puts the person to sleep.
Angiogenesis (an-gee-o-GEN-e-sis): Blood vessel formation, which usually accompanies the growth of malignant tissue.
Angiogram (AN-jee-o-gram): An x-ray of blood vessels; the patient receives an injection of dye to outline the vessels on the x-ray.
Angiography (an-jee-O-gra-fee): A procedure to x-ray blood vessels. The blood vessels can be seen because of an injection of a dye that shows up in the x-ray pictures.
Angiosarcoma (AN-jee-o-sar-KO-ma): A type of cancer that begins in the lining of blood vessels.
Antiandrogen (an-tee-AN-dro-jen): A drug that blocks the action of male sex hormones.
Antibiotics (an-ti-by-AH-tiks): Drugs used to treat infection.
Antibody (AN-ti-BOD-ee): A protein produced by certain white blood cells in response to a foreign substance (antigen). Each antibody can bind only to a specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies disable antigens directly. Others make the antigen more vulnerable to destruction by white blood cells.
Anticonvulsant (an-ti-kon-VUL-sant): Medicine to stop, prevent, or control seizures (convulsions).
Antigen: Any foreign or "non-self" substance that, when introduced into the body, causes the immune system to create an antibody.
Antithymocyte globulin (anti-THIGH-moe-site GLA-bu-lin): A protein preparation used to prevent and treat graft-versus-host disease.
Anus (AY-nus): The opening of the rectum to the outside of the body.
Anal cancer: Anal cancer, an uncommon cancer, is a disease in which cancer (malignant) cells are found in the anus. The anus is the opening at the end of the rectum (the end part of the large intestine) through which body waste passes.
Aplastic anemia: A deficiency of certain parts of the blood caused by a failure of the bone marrow's ability to generate cells.
Apoptosis (ay-paw-TOE-sis): A normal cellular process involving a genetically programmed series of events leading to the death of a cell.
Areola (a-REE-oe-la): The area of dark-colored skin that surrounds the nipple.
Arterial embolization (ar-TEE-ree-al EM-bo-lih-ZAY-shun): Blocking an artery so that blood cannot flow to the tumor.
Arteriogram (ar-TEER-ee-o-gram): An x-ray of blood vessels, which can be seen after an injection of a dye that shows up in the x-ray pictures.
Asbestos (as-BES-tus): A natural material that is made up of tiny fibers. If the fibers are inhaled, they can lodge in the lungs and lead to cancer.
Ascites (a-SYE-teez): Abnormal buildup of fluid in the abdomen.
Aspiration (as-per-AY-shun): Removal of fluid from a lump, often a cyst, with a needle and a syringe.
Astrocytoma (as-tro-sye-TOE-ma): A type of brain tumor that begins in the brain or spinal chord in small, star-shaped cells called astrocytes.
Asymptomatic: Presenting no signs or symptoms of disease.
Astrocytoma: Astrocytomas are tumors that start in brain cells called astrocytes. There are different kinds of astrocytomas, which are defined by how the cancer cells look under a microscope.
Ataxic gait (ah-TAK-sik): Awkward, uncoordinated walking.
Atypical hyperplasia (hy-per-PLAY-zha): A benign (noncancerous) condition in which tissue has certain abnormal features.
Autologous bone marrow transplantation (aw-TAHL-o-gus): A procedure in which bone marrow is removed from a patient and then is given back to the patient following intensive treatment.
Autologous transplant: In this type of transplant, the patient's own blood or bone marrow cells, collected earlier, are transplanted back into the patient's body.
Axilla (ak-SIL-a): The underarm.
Axillary (AK-sil-air-ee): Pertaining to the lymph nodes under the arm.
Axillary dissection (AK-sil-air-ee): Surgery to remove lymph nodes under the arm.
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B cells: White blood cells that develop in the bone marrow and are the source of antibodies. Also known as B lymphocytes.
Barium enema: A series of x-rays of the lower intestine. The x-rays are taken after the patient is given an enema with a white, chalky solution that contains barium. The barium outlines the intestines on the x-rays.
Barium solution: A liquid containing barium sulfate that is used in x-rays to highlight parts of the digestive system.
Barrett's esophagus: A change in the cells of the tissue that lines the bottom of the esophagus. The esophagus may become irritated when the contents of the stomach back up (reflux). Reflux that happens often over a long period of time can lead to Barrett's esophagus.
Basal cell carcinoma: This type of skin cancer affects the basal cells found in the top layer of skin, called the epidermis.
Basal cells: Small, round cells found in the lower part, or base, of the epidermis, the outer layer of the skin.
Basophil: A type of white blood cell. Basophils are granulocytes.
BCG (Bacillus Calmette-Guerin): A substance that activates the immune system. Filling the bladder with a solution of BCG is a form of biological therapy for superficial bladder cancer.
Benign: Benign refers to cells or tumors that are not cancerous; they do not invade nearby tissue or spread to other parts of the body.
Benign prostatic hyperplasia (hy-per-PLAY-zha): A noncancerous condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy or BPH.
Benign tumor (beh-NINE): A noncancerous growth that does not spread to other parts of the body.
Beta-carotene: A substance from which vitamin A is formed; a precursor of vitamin A.
Bilateral: Affecting the right and left side of body.
Bile: A yellow or orange fluid made by the liver. Bile is stored in the gallbladder. It passes through the common bile duct into the duodenum, where it helps digest fat.
Biological response modifiers (by-o-LOJ-i-kal): Substances that stimulate the body's response to infection and disease. The body naturally produces small amounts of these substances. Scientists can produce some of them in the laboratory in large amounts and use them in cancer treatment. Also called BRMs.
Biological therapy (by-o-LOJ-i-kul): The use of the body's immune system, either directly or indirectly, to fight cancer or to lessen side effects that may be caused by some cancer treatments. Also known as immunotherapy, biotherapy, or biological response modifier therapy.
Biopsy (BYE-ahp-see): The removal of a sample of tissue, which is then examined under a microscope to check for cancer cells.
Bioimmunotherapy: Treatment to stimulate or restore the ability of the immune system to fight infection and disease.
Biopsy: The removal of a sample of tissue, which is then examined under a microscope to check for cancer cells. When only a sample of tissue is removed, the procedure is called incisional biopsy; when the whole tumor is removed, it is excisional biopsy. Removing tissue or fluid with a needle is called needle biopsy or needle aspiration.
Bladder: The hollow organ that stores urine.
Bladder cancer: Bladder cancer is a disease in which cancer (malignant) cells are found in the bladder. The bladder, a hollow organ in the lower part of the abdomen, stores urine.
Blasts: Immature blood cells.
Blast phase: Refers to advanced chronic myelogenous leukemia. In this phase, the number of immature, abnormal white blood cells in the bone marrow and blood is extremely high. Also called blast crisis.
Blood-brain barrier: A network of blood vessels with closely spaced cells that makes it difficult for potentially toxic substances (such as anticancer drugs) to penetrate the blood vessel walls and to enter the brain.
Bone marrow: The soft, spongy tissue in the center of large bones that produces white blood cells, red blood cells, and platelets.
Bone marrow aspiration (as-per-AY-shun) or biopsy (BY-op-see): The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope to see whether cancer cells are present.
Bone marrow biopsy (BYE-ahp-see): The removal of a sample of tissue from the bone marrow with a large needle. The cells are checked to see whether they are cancerous. If cancerous plasma cells are found, the pathologist estimates how much of the bone marrow is affected. Bone marrow biopsy is usually done at the same time as bone marrow aspiration.
Bone marrow transplantation (trans-plan-TAY-shun): A procedure in which doctors replace marrow destroyed by treatment with high doses of anticancer drugs or radiation. The replacement marrow may be taken from the patient before treatment or may be donated by another person.
Bone scan: A technique to create images of bones on a computer screen or on film. A small amount of radioactive material is injected and travels through the bloodstream. It collects in the bones, especially in abnormal areas of the bones, and is detected by a scanner.
Bowel: Another name for the intestine. There is both a small and a large bowel.
Brachytherapy: A type of radiotherapy in which the radiation source is placed on the surface of the body or a short distance away form the area to be treated.
- Astrocytoma: Astrocytomas are tumors that start in brain cells called astrocytes. There are different kinds of astrocytomas, which are defined by how the cancer cells look under a microscope.
- Ependymoma: Ependymal tumors are tumors that begin in the ependyma, the cells that line the passageways in the brain where special fluid that protects the brain and spinal cord (called cerebrospinal fluid) is made and stored. There are different kinds of ependymal tumors, which are defined by how the cells look under a microscope.
- Glioblastoma: Glioblastoma multiformes are tumors that grow very quickly and have cells that look very different from normal cells. Glioblastoma multiforme is also called grade IV astrocytoma.
- Medulloblastoma: Medulloblastomas are brain tumors that begin in the lower part of the brain. They are almost always found in children or young adults. This type of cancer may spread from the brain to the spine.
Brachytherapy (BRAK-i-THER-a-pee): Internal radiation therapy using an implant of radioactive material placed directly into or near the tumor.
Brain stem: The stemlike part of the brain that is connected to the spinal cord.
Brain stem glioma (glee-O-ma): A type of brain tumor that occurs in the lowest, stemlike part of the brain.
BRCA1: A gene located on chromosome 17 that normally helps to restrain cell growth. Inheriting an altered version of BRCA1 predisposes an individual to breast, ovary, and prostate cancer.
Breast reconstruction: Surgery to rebuild a breast's shape after a mastectomy.
Bronchi (BRONK-eye): Air passage that leads from the windpipe to the lungs.
Bronchioles (BRON-kee-ols): The tiny branches of air tubes in the lungs.
Bronchitis (BRON-KYE-tis): Inflamation (swelling and reddening) of the bronchi.
Bronchoscope (BRON-ko-skope): A flexible, lighted instrument used to examine the trachea and bronchi, the air passages that lead into the lungs.
Bronchoscopy (bron-KOS-ko-pee): A test that permits the doctor to see the breathing passages through a lighted tube.
Buccal mucosa (BUK-ul myoo-KO-sa): The inner lining of the cheeks and lips.
Burkitt's lymphoma: A type of non-Hodgkin's lymphoma that most often occurs in young people between the ages of 12 and 30. The disease usually causes a rapidly growing tumor in the abdomen.
Bypass: A surgical procedure in which the doctor creates a new pathway for the flow of body fluids.
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Calcium (KAL-see-um): A mineral found mainly in the hard part of bones.
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.
Cancer screening: Different tests may show whether a person has a higher than normal risk for getting certain types of cancer. The person's family history and medical history are also key parts of the cancer screening process.
Carcinogen (kar-SIN-o-jin): Any substance that is known to cause cancer.
Carcinogenesis: The process by which normal cells are transformed into cancer cells.
Carcinoma (kar-sin-O-ma): Cancer that begins in the lining or covering of an organ.
Carcinoma in situ (kar-sin-O-ma in SY-too): Cancer that involves only the cells in which it began and has not spread to other tissues.
Cartilage (KAR-ti-lij): Firm, rubbery tissue that cushions bones at joints. A more flexible kind of cartilage connects muscles with bones and makes up other parts of the body, such as the larynx and the outside of the ears.
Catheter (KATH-et-er): A tube that is placed in a blood vessel to provide a pathway for drug or nutrients.
Cauterization (KAW-ter-i-ZAY-shun): The use of heat to destroy abnormal cells.
CEA assay: A laboratory test to measure the level of carcinoembryonic antigen (CEA), a substance that is sometimes found in an increased amount in the blood of patients with certain cancers.
Cell: The basic unit of any living organism.
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.
Cellular adhesion: The close adherence (bonding) to adjoining cell surfaces.
Cervical cancer: Cancer of the cervix, a common kind of cancer in women, is a disease in which cancer (malignant) cells are found in the tissues of the cervix. The cervix is the opening of the uterus (womb).
Central nervous system: The brain and spinal cord. Also called CNS.
Cerebellum (sair-uh-BELL-um): The portion of the brain in the back of the head between the cerebrum and the brain stem.
Cerebral hemispheres (seh-REE-bral HEM-iss-feerz): The two halves of the cerebrum.
Cerebrospinal fluid (seh-REE-bro-spy-nal): The watery fluid flowing around the brain and spinal cord. Also called CSF.
Cerebrum (seh-REE-brum): The largest part of the brain. It is divided into two hemispheres, or halves.
Cervical intraepithelial neoplasia (SER-vih-kul in-tra-eh-pih-THEEL-ee-ul NEE-o-play-zha): 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. Also called CIN.
Cervix (SER-viks): The lower, narrow end of the uterus that forms a canal between the uterus and vagina.
Chemoprevention: The use of certain drugs may prevent some types of cancer in people at high risk for the disease. Drugs may also be used to halt disease in its very early stages.
Chemotherapy: Chemotherapy is the use of drugs to try to stop or slow the growth of cancer cells. It often is used in combination with other treatments (radiation therapy or surgery). Chemotherapy can be administered orally (capsule, pill, or liquid), by injection into a vein, artery, or muscle, or by intravenous (IV) drip. Chemotherapy affects rapidly growing cells, which may be cancerous or normal (such as hair cells, bone marrow). Some side effects of chemotherapy include hair loss, mouth sores, nausea, and vomiting.
Chondrosarcoma: This is cancer of the cartilage cells, occurring mainly in the pelvis, femur, and shoulder areas.
Cholangiosarcoma (ko-LAN-jee-o-sar-KO-ma): A type of cancer that begins in the bile ducts.
Chordoma (kor-DO-ma): A form of bone cancer that usually starts in the lower spinal column.
Chromosome (KRO-mo-soam): Part of a cell that contains genetic information. Normally, human cells contain 46 chromosomes that appear as a long thread inside the cell.
Chronic leukemia (KRON-ik): Leukemia that progresses slowly.
Chronic phase (KRON-ik): Refers to the early stages of chronic myelogenous leukemia or chronic lymphocytic leukemia. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than normal, but lower than in the accelerated or blast phase.
Clinical Trial: Clinical trials are research studies that evaluate new treatment options. Clinical trials are conducted in health care settings with voluntary patient-participants.
CNS (central nervous system): The brain and the spinal cord.
CNS prophylaxis (pro-fi-LAK-sis): Chemotherapy or radiation therapy to the central nervous system (CNS). This is 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.
Colectomy (ko-LEK-to-mee): An operation to remove all or part of the colon. In a partial colectomy, the surgeon removes only the cancerous part of the colon and a small amount (called a margin) of surrounding healthy tissue.
Colon (KO-lun): The long, coiled, tubelike organ that removes water from digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.
Colonoscope (ko-LON-o-skope): A flexible, lighted instrument used to view the inside of the colon.
Colonoscopy (ko-lon-OS-ko-pee): An examination in which the doctor looks at the colon through a flexible, lighted instrument called a colonoscope.
Colony-stimulating factors: Substances that stimulate the production of blood cells. Treatment with colony-stimulating factors (CSF) can help the blood-forming tissue recover from the effects of chemotherapy and radiation therapy.
Colorectal (ko-lo-REK-tul): Related to the colon and/or rectum.
Colon cancer: Cancer of the colon, a common form of cancer, is a disease in which cancer (malignant) cells are found in the tissues of the colon. The colon is part of the body's digestive system. The last 6 feet of intestine is called the large bowel or colon.
Colostomy (ko-LOS-to-mee): An opening created by a surgeon 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.
Colposcopy (kul-POSS-ko-pee): A procedure in which a lighted magnifying instrument (called a colposcope) is used to examine the vagina and cervix.
Combination chemotherapy: Treatment in which two or more chemicals are used to obtain more effective results.
Common bile duct: Bile ducts are passageways that carry bile. Two major bile ducts come together into a "trunk"-the common bile duct which empties into the upper part of the small intestine (the part next to the stomach).
Computed tomography (tom-OG-rah-fee): An x-ray procedure that uses a computer to produce a detailed picture of a cross section of the body; also called CAT or CT scan.
Condylomata acuminata (kon-di-LOW-ma-ta a-kyoo-mi-NA-ta): Genital warts caused by certain human papillomaviruses.
Conization (ko-ni-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.
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.
Control Group: The control group of patients in a clinical trial receives current standard care and/or placebo. Results of the control group are compared to results of the treatment group--the patients who received the new treatment. When no standard care exists for a condition, the control group would receive no treatment, which may be a placebo. Patients are told if this is a possibility. No patient is placed in a control group without treatment if any beneficial treatment is known and most cancer treatment clinical trials do not use placebo because standard care is available to use as a control.
Corpus: The body of the uterus.
Craniopharyngioma (KRAY-nee-o-fah-rin-jee-O-ma): A type of brain tumor that develops in the region of the pituitary gland near the hypothalamus, the area of the brain that controls body temperature, hunger, and thirst. These tumors are usually benign, but are sometimes considered malignant because they can press on or damage the hypothalamus and affect vital functions.
Craniotomy (kray-nee-OT-o-mee): An operation in which an opening is made in the skull so the doctor can reach the brain.
Cryosurgery (KRY-o-SER-jer-ee): Treatment performed with an instrument that freezes and destroys abnormal tissues.
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; also called undescended testicles.
CT (or CAT) scan: A series of detailed pictures of areas inside the body; the pictures are created by a computer linked to an x-ray machine. Also called computed tomography scan or computed axial tomography scan.
Curettage (kyoo-re-TAHZH): Removal of tissue with a curette.
Curette (kyoo-RET): A spoon-shaped instrument with a sharp edge.
Cutaneous (kyoo-TAY-nee-us): Related to the skin.
Cutaneous T-cell lymphoma: Cutaneous T-cell lymphoma is a disease in which certain cells of the lymph system (called T-lymphocytes) become cancer (malignant) and affect the skin. Lymphocytes are infection-fighting white blood cells that are made in the bone marrow and by other organs of the lymph system. T-cells are special lymphocytes that help the body's immune system kill bacteria and other harmful things in the body.
Cyst (sist): A sac or capsule filled with fluid.
Cystectomy (sis-TEK-to-mee): Surgery to remove the bladder.
Cystoscope (SIS-to-skope): An instrument that allows the doctor to see inside the bladder and remove tissue samples or small tumors.
Cystoscopy (sist-OSS-ko-pee): A procedure in which the doctor inserts a lighted instrument into the urethra (the tube leading from the bladder to the outside of the body) to look at the bladder.
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Dermatologist (der-ma-TOL-o-jist): A doctor who specializes in the diagnosis and treatment of skin problems.
Dermis (DER-mis): The lower or inner layer of the two main layers of cells that make up the skin.
Diabetes (dye-a-BEE-teez): A disease in which the body does not use sugar properly. (Many foods are converted into sugar, a source of energy for cells.) As a result, the level of sugar in the blood is too high. This disease occurs when the body does not produce enough insulin or does not use it properly.
Diagnosis: The process of indentifying a disease by the signs and symptoms.
Dialysis (dy-AL-i-sis): The process of cleansing the blood by passing it through a special machine. Dialysis is necessary when the kidneys are not able to filter the blood.
Diaphanography (DY-a-fan-OG-ra-fee): An exam that involves shining a bright light through the breast to reveal features of the tissues inside. This technique is under study; its value in detecting breast cancer has not been proven. Also called transillumination.
Diaphragm (DY-a-fram): The thin muscle below the lungs and heart that separates the chest from the abdomen.
Diathermy (DIE-a-ther-mee): The use of heat to destroy abnormal cells. Also cauterization or electrodiathermy.
Diethylstilbestrol (die-ETH-ul-stil-BES-trol): A drug that was once widely prescribed to prevent miscarriage. Also called DES.
Differentiation: In cancer, refers to how mature (developed) the cancer cells are in a tumor. Differentiated tumor cells resemble normal cells and grow at a slower rate than undifferentiated tumor cells, which lack the structure and function of normal cells and grow uncontrollably.
Digestive system: The organs that take in food and turn it into products that the body can use to stay healthy. Waste products the body cannot use leave the body through bowel movements. The digestive system includes the salivary glands, mouth, esophagus, stomach, liver, pancreas, gallbladder, intestines, and rectum.
Digestive tract (dye-JES-tiv): The organs through which food passes when we eat. These are the mouth, esophagus, stomach, small and large intestines, and rectum.
Digital rectal exam: An exam to detect cancer. The doctor inserts a lubricated, gloved finger into the rectum and feels for abnormal areas. Also called DRE.
Dilation and Curettage (di-LAY-shun and KYOO-re-tahzh): A minor operation in which the cervix is expanded enough (dilation) to permit the cervical canal and uterine lining to be scraped with a spoon-shaped instrument called a curette (curettage). This procedure also is called D and C.
Dilator (DIE-lay-tor): A device used to stretch or enlarge an opening.
Double-blinded: Double-blinded clinical trials are those in which the patients and the scientist do not know which treatment each patient is receiving. Blinding a study prevents personal bias from influencing their reactions and the study results. Treatment can be quickly identified, if necessary, by a special code.
DNA: The protein that carries genetic information; every cell contains a strand of DNA (deoxyribonucleic acid).
Douching (DOO-shing): Using water or a medicated solution to clean the vagina and cervix.
Dry orgasm: Sexual climax without the release of semen.
Duct (dukt): A tube through which body fluids pass.
Ductal carcinoma in situ: About 15%-20% of breast cancers are sometimes called carcinoma in situ. They may be either ductal carcinoma in situ (sometimes called intraductal carcinoma) or lobular carcinoma in situ. Even though it is referred to as a cancer, it is not actually cancer. However, patients with this condition have a 25% chance of developing breast cancer in either breast in the next 25 years.
Dumping syndrome: A group of symptoms that occur when food or liquid enters the small intestine too rapidly. These symptoms include cramps, nausea, diarrhea, and dizziness.
Duodenum (doo-o-DEE-num): The first part of the small intestine.
Dysplasia (dis-PLAY-zha): Abnormal cells that are not cancer.
Dysplastic nevi: (dis-PLAS-tik NEE-vye): Atypical moles; moles whose appearance is different from that of common moles. Dysplastic nevi are generally larger than ordinary moles and have irregular and indistinct borders. Their color often is not uniform, and ranges from pink or even white to dark brown or black; they usually are flat, but parts may be raised above the skin surface.
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Edema (eh-DEE-ma); Swelling; an abnormal buildup of fluid.
Ejaculation: The release of semen through the penis during orgasm.
Electrodesiccation (e-LEK-tro-des-i-KAY-shun): Use of an electric current to destroy cancerous tissue and control bleeding.
Electrolarynx (e-LEK-tro-LAR-inks): A battery-operated instrument that makes a humming sound to help laryngectomees talk.
Embolization (EM-bo-li-ZAY-shun): Blocking an artery so that blood cannot flow to the tumor.
Encapsulated (en-KAP-soo-lay-ted): Confined to a specific area; the tumor remains in a compact form.
Endometrial cancer: Cancer of the endometrium, a common kind of cancer in women, is a disease in which cancer (malignant) cells are found in the lining of the uterus (endometrium). The uterus is the hollow, pear-shaped organ where a baby grows. Cancer of the endometrium is different from cancer of the muscle of the uterus, which is called sarcoma of the uterus.
Endoscopy: A procedure in which the doctor looks inside the body through a lighted tube called an endoscope.
Endocervical curettage (en-do-SER-vi-kul kyoo-re-TAZH): The removal of tissue from the inside of the cervix using a spoon-shaped instrument called a curette.
Endocrinologist (en-do-kri-NOL-o-jist): A doctor that specializes in diagnosing and treating hormone disorders.
Endometriosis (en-do-mee-tree-O-sis): A benign condition in which tissue that looks like endometrial tissue grows in abnormal places in the abdomen.
Endometrium (en-do-MEE-tree-um): The layer of tissue that lines the uterus.
Endoscope (EN-do-skope): A thin, lighted tube through which a doctor can look at tissues inside the body.
Endoscopic retrograde cholangiopancreatography (en-do-SKAH-pik RET-ro-grade ko-LAN-jee-o-PAN-kree-a-TAW-gra-fee): A procedure to x-ray the common bile duct. Also called ERCP.
Endoscopy (en-DOS-ko-pee): An examination of the esophagus and stomach using a thin, lighted instrument called an endoscope.
Ependymoma: Ependymal tumors are tumors that begin in the ependyma, the cells that line the passageways in the brain where special fluid that protects the brain and spinal cord (called cerebrospinal fluid) is made and stored. There are different kinds of ependymal tumors, which are defined by how the cells look under a microscope.
Epidermis (ep-i-DER-mis): The upper or outer layer of the two main layers of cells that make up the skin.
Epidermoid carcinoma (ep-i-DER-moyd): A type of lung cancer in which the cells are flat and look like fish scales. Also called squamous cell carcinoma.
Epiglottis (ep-i-GLOT-is): The flap that covers the trachea during swallowing so that food does not enter the lungs.
Epithelial carcinoma (ep-i-THEE-lee-ul kar-si-NO-ma): Cancer that begins in the cells that line an organ.
Epithelium (EP-i-THEE-lee-um): A thin layer of tissue that covers organs, glands, and other structures in the body.
ERCP (endoscopic retrograde cholangiopancreatography) (en-do-SKOP-ik RET-ro-grade ko-LAN-gee-o-PAN-kree-a-TOG-ra-fee): A procedure to x-ray the common bile duct.
Erythrocytes (e-RITH-ro-sites): Cells that carry oxygen to all parts of the body. Also called red blood cells (RBCs).
Erythroleukemia (e-RITH-ro-loo-KEE-mee-a): Leukemia that develops in erythrocytes. In this rare disease, the body produces large numbers of abnormal red blood cells.
Erythroplakia (eh-RITH-ro-PLAY-kee-a): A reddened patch with a velvety surface found in the mouth.
Esophageal speech (e-SOF-a-JEE-al): Speech produced with air trapped in the esophagus and forced out again.
Esophagectomy (e-soff-a-JEK-to-mee): An operation to remove a portion of the esophagus.
Esophagoscopy (e-soff-a-GOSS-ko-pee): Examination of the esophagus using a thin, lighted instrument.
Esophagram (e-SOFF-a-gram): A series of x-rays of the esophagus. The x-ray pictures are taken after the patient drinks a solution that coats and outlines the walls of the esophagus. Also called a barium swallow.
Esophagus (e-SOF-a-gus): The muscular tube through which food passes from the throat to the stomach.
Estrogen (ES-tro-jin): A female hormone.
Esophageal cancer (also see): Cancer of the esophagus is a disease in which cancer (malignant) cells are found in the tissues of the esophagus. The esophagus is the hollow tube that carries food and liquid from the throat to the stomach.
Etiology: The study of the causes of abnormal condition or disease.
Ewing's sarcoma: Ewing's sarcoma/primitive neuroepithelial tumor is a rare disease in which cancer (malignant) cells are found in the bone. The most common areas in which it occurs are the pelvis, the thigh bone (femur), the upper arm bone (humerus), and the ribs. Ewing's sarcoma/primitive neuroepithelial tumor most frequently occurs in teenagers.
External radiation: Radiation therapy that uses a machine to aim high-energy rays at the cancer.
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Fallopian tubes (fa-LO-pee-in): Tubes on each side of the uterus through which an egg moves from the ovaries to the uterus.
Familial polyposis (pol-i-PO-sis): An inherited condition in which several hundred polyps develop in the colon and rectum.
Fecal occult blood test (FEE-kul o-KULT): A test to check for hidden blood in stool. (Fecal refers to stool. Occult means hidden.)
Fertility (fer-TIL-i-tee): The ability to produce children.
Fetus (FEET-us): The unborn child developing in the uterus.
Fiber: The parts of fruits and vegetables that cannot be digested. Also called bulk or roughage.
Fibroid (FY-broid): A benign uterine tumor made up of fibrous and muscular tissue.
Fibrosarcoma: This malignant tumor originates from cells called fibroblasts, which produce collagen. Collagen is a fibrous protein found in skin, tendons, muscle, bone, and cartilage.
Fluoroscope (FLOOR-o-skope): An x-ray machine that makes it possible to see internal organs in motion.
Fluoroscopy (Floor-OS-ko-pee): An x-ray procedure that makes it possible to see internal organs in motion
Fluorouracil (floo-ro-YOOR-a-sil): An anticancer drug. Its chemical name is 5-fluorouracil, commonly called 5-FU.
Follicles (FAHL-ih-kuls): Shafts through which hair grows.
Food and Drug Administration (FDA): The United States Food and Drug Administration (FDA) is a public health agency, charged with protecting U.S. consumers by enforcing the Federal Food, Drug, and Cosmetic Act and related public health laws. In deciding whether to approve new drugs, the FDA itself does not conduct research; rather it examines the results of studies conducted by the manufacturer. The FDA must determine that the new drug produces the expected benefits without causing side effects that outweigh those benefits.
Fractionation: Dividing the total dose of radiation therapy into several smaller, equal doses delivered over a period of several days.
Fulguration (ful-gyoor-AY-shun): Destroying tissue using an electric current.
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Gallbladder (GAWL-blad-er): The pear-shaped organ that sits below the liver. Bile is stored in the gallbladder.
Gamma knife: Radiation therapy in which high-energy rays are aimed at a tumor from many angles in a single treatment session.
Gastrectomy (gas-TREK-to-mee): An operation to remove all or part of the stomach.
Gastric (GAS-trik): Having to do with the stomach.
Gastric atrophy (GAS-trik AT-ro-fee): A condition in which the stomach muscles shrink and become weak. It results in a lack of digestive juices.
Gastric cancer: Cancer of the stomach, also called gastric cancer, is a disease in which cancer (malignant) cells are found in the tissues of the stomach.
Gastroenterologist (GAS-tro-en-ter-OL-o-jist): A doctor who specializes in diagnosing and treating disorders of the digestive system.
Gastrointestinal tract (GAS-tro-in-TES-ti-nul): The part of the digestive tract where the body processes food and eliminates waste. It includes the esophagus, stomach, liver, small and large intestines, and rectum.
Gastroscope (GAS-tro-skope): A thin, lighted instrument to view the inside of the stomach.
Gastroscopy (gas-TROS-ko-pee): An examination of the stomach with a gastroscope, an instrument to view the inside of the stomach.
Gene: The biological or basic unit of heredity found in all cells in the body.
Gene deletion: The total loss or absence of a gene.
Gene therapy: Treatment that alters genes (the basic units of heredity found in all cells in the body). In studies of gene therapy for cancer, researchers are trying to improve the body's natural ability to fight the disease or to make the tumor more sensitive to other kinds of therapy.
Genetic-Inherited: having to do with information that is passed from parents to children through DNA in the genes.
Genetic testing: Specific tests can be done to see if a person has changes in certain genes that are known to be associated with cancer.
Genitourinary system (GEN-i-toe-YOO-rin-air-ee): The parts of the body that play a role in reproduction, in getting rid of waste products in the form of urine, or in both.
Germ cells: The reproductive cells of the body specifically, either egg or sperm cells.
Germ cell tumor (see also): Germ cell tumors arise from the sex cells. There are different kinds of germ cells, including germinomas, embryonal carcinomas, choriocarcinomas, and teratomas.
Germinoma (jer-mih-NO-ma): The most frequent type of germ cell tumor in the brain.
Germline mutation: See hereditary mutation.
Gestational trophoblastic disease: Gestational trophoblastic tumor, a rare cancer in women, is a disease in which cancer (malignant) cells grow in the tissues that are formed following conception (the joining of sperm and egg). Gestational trophoblastic tumors start inside the uterus, the hollow, muscular, pear-shaped organ where a baby grows. This type of cancer occurs in women during the years when they are able to have children.
Gland: An organ that produces and releases one or more substances for use in the body. Some glands produce fluids that affect tissues or organs. Others produce hormones or participate in blood production.
Glioblastoma: Glioblastoma multiformes are tumors that grow very quickly and have cells that look very different from normal cells. Glioblastoma multiforme is also called grade IV astrocytoma.
Glioblastoma multiforme (glee-o-blast-TO-ma mul-tih-FOR-may): A type of brain tumor that forms in the nervous (glial) tissue of the brain.
Glioma (glee-O-ma): A name for brain tumors that begin in the glial cells, or supportive cells, in the brain. "Glia" is the Greek word for glue.
Glottis (GLOT-is): The middle part of the larynx; the area where the vocal cords are located.
Grade: Describes how closely a cancer resembles normal tissue of its same type, and the cancer's probable rate of growth.
Grading: A system for classifying cancer cells in terms of how malignant or aggressive they appear microscopically. The grading of a tumor indicates how quickly cancer cells are likely to spread and plays a role in treatment decisions.
Graft: Healthy skin, bone, or other tissue taken from one part of the body to replace diseased or injured tissue removed from another part of the body.
Graft-versus-host disease: A reaction of donated bone marrow against a patient's own tissue. Also called GVHD.
Granulocyte (GRAN-yoo-lo-site): A type of white blood cell. Neutrophils, eosinophils, and basophils are granulocytes.
Groin: The area where the thigh meets the hip.
GVHD (graft-versus-host disease): A reaction of donated bone marrow against a patient's own tissue.
Gynecologic oncologists (guy-ne-ko-LA-jik on-KOL-o-jists): Doctors who specialize in treating cancers of the female reproductive organs.
Gynecologist (guy-ne-KOL-o-jist): A doctor who specializes in treating diseases of the female reproductive organs.
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Hair follicles (FOL-i-kuls): The sacs in the scalp from which hair grows.
Hairy cell leukemia: A rare type of chronic leukemia in which the abnormal white blood cells appear to be covered with tiny hairs.
Helicobacter pylori (HEEL-i-ko-BAK-ter pie-LOR-ee): Bacteria that cause inflammation and ulcers in the stomach.
Hematogenous: Orginating in the blood, or disseminated by the circulation or through the bloodstream.
Hematologist (hee-ma-TOL-o-jist): A doctor who specializes in treating diseases of the blood.
Hepatitis (hep-a-TYE-tis): Inflammation of the liver. Hepatitis B: A type of hepatitis that is carried and passed on through the blood. It can be passed on through sexual contact or through the use of "dirty" (bloody) needles.
Hepatoblastoma (HEP-a-to-blas-TO-ma): A type of liver tumor that occurs in infants and children.
Hepatocellular carcinoma (HEP-a-to-SEL-yoo-ler kar-si-NO-ma): The most common type of primary liver cancer.
Hepatocyte (HEP-a-to-site): A liver cell.
Hepatoma (HEP-a-TO-ma): A liver tumor.
Hereditary mutation: A gene change in the body's reproductive cells (egg or sperm) that becomes incorporated into the DNA of every cell in the body of offspring; hereditary mutations are passed on from parents to offspring.
Herpes virus (HER-peez-VY-rus): A member of the herpes family of viruses. One type of herpesvirus is sexually transmitted and causes sores on the genitals.
HER-2/neu: Oncogene found in some breast and ovarian cancer patients that is associated with a poor prognosis.
Hodgkin's disease (see also): Hodgkin's disease is a type of lymphoma. Lymphomas are cancers that develop in the lymph system, part of the body's immune system.
Hormonal therapy: Treatment of cancer by removing, blocking, or adding hormones.
Hormone receptor test: A test to measure the amount of certain proteins, called hormone receptors, in breast cancer tissue. Hormones can attach to these proteins. A high level of hormone receptors means hormones probably help the cancer grow. Hormone therapy: Treatment that prevents certain cancer cells form getting the hormones they need to grow.
Hormones: Chemicals produced by glands in the body and circulate in the bloodstream. Hormones control the actions of certain cells or organs.
Human papillomaviruses (pap-i-LOW-ma VY-rus-ez): Viruses that generally cause warts. Some papillomaviruses are sexually transmitted. Some of these sexually transmitted viruses cause wartlike growths on the genitals, and some are thought to cause abnormal changes in cells of the cervix.
Humidifier (hyoo-MID-ih-fye-er): A machine that puts moisture in the air.
Hydrocephalus (hy-dro-SEF-uh-lus): The abnormal buildup of cerebrospinal fluid in the ventricles of the brain.
Hypercalcemia (hy-per-kal-SEE-mee-a): A higher-than-normal level of calcium in the blood. This condition can cause a number of symptoms, including loss of appetite, nausea, thirst, fatigue, muscle weakness, restlessness, and confusion.
Hyperfractionation: A way of giving radiation therapy in smaller-than-usual doses two or three times a day.
Hyperplasia (hye-per-PLAY-zha): A precancerous condition in which there is an increase in the number of normal cells lining the uterus.
Hyperthermia (hy-per-THER-mee-a): Treatment that involves heating a tumor.
Hypothalamus (hy-po-THAL-uh-mus): The area of the brain that controls body temperature, hunger, and thirst.
Hysterectomy (hiss-ter-EK-to-mee): An operation in which the uterus and cervix are removed.
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Ileostomy (il-ee-OS-to-mee): An opening created by a surgeon into the ileum, part of the small intestine, from the outside of the body. An ileostomy provides a new path for waste material to leave the body after part of the intestine has been removed.
Imaging: Tests that produce pictures of areas inside the body.
Immune system (im-YOON): The complex group of organs and cells that defends the body against infection or disease. Immunodeficiency: A lowering of the body's ability to fight off infection and disease.
Immunology: A science that deals with the study of the body's immune system.
Immunosuppression: The use of drugs or techniques to suppress or interfere with the body's immune system and its ability to fight infections or disease. Immunosuppression may be deliberate, such as in preparation for bone marrow or other organ transplantation to prevent rejection by the host of the donor tissue, or incidental, such as often results from chemotherapy for the treatment of cancer.
Immunotherapy: Immunotherapy (also known as biological therapy) is a relatively new form of cancer therapy that tries to enhance the body's own defenses to fight cancer cells. Scientists try to stimulate or replace immune system cells to help destroy or prevent the growth of cancer cells. Biological agents that have shown success in triggering an immune response against some cancers include interferons, interleukins, colony-stimulating factors, T cells, tumor vaccines, tumor necrosis factors, and gene therapy.
Immuno-oncology: An innovative field of cancer research and treatment which involves agents whose primary mechanism is to work directly with the body's immune system to fight cancer.
Implant (or internal) radiation: Internal radiation therapy that places radioactive materials in or close to the cancer.
Impotent (IM-po-tent): Inability to have an erection and/or ejaculate semen.
Incidence: The number of new cases of a disease diagnosed each year.
Incision (in-SI-zhun): A cut made in the body during surgery.
Incontinence (in-kON-ti-nens): Inability to control the flow of urine from the bladder. Infertility: The inability to produce children.
Infiltrating cancer: See invasive cancer.
Inflammatory breast cancer: A rare type of breast cancer in which cancer cells block the lymph vessels in the skin of the breast. The breast becomes red, swollen, and warm, and the skin of the breast may appear pitted or have ridges.
Informed Consent: Informed consent is a process by which a person learns the details about a clinical trial and agrees to participate. The scientist explains the purpose of the trial, expected benefits and known risks, and what is expected of the patient-participant. The scientist also answers any questions. If the patient agrees to participate in the trial, she or he signs an informed consent document acknowledging that the trial was explained and is understood.
Inguinal orchiectomy (IN-gwin-al or-kee-EK-to-mee): Surgery to remove the testicle through the groin.
Insulin (IN-su-lin): A hormone made by the islet cells of the pancreas. Insulin controls the amount of sugar in the blood.
Interferon (in-ter-FEER-on): A type of biological response modifier (a substance that can improve the body's natural response to disease). It stimulates the growth of certain disease-fighting blood cells in the immune system.
Interleukin (in-ter-LOO-kin): A substance used in biological therapy. Interleukins stimulate the growth and activities of certain kinds of white blood cells.
Interleukin-2 (in-ter-LOO-kin): A type of biological response modifier (a substance that can improve the body's natural response to disease). It stimulates the growth of certain blood cells in the immune system that can fight cancer. Also called IL-2.
Internal radiation (ray-dee-AY-shun): Radiation therapy that uses radioactive materials placed in or near the tumor.
Intestine (in-TES-tin): The long, tube-shaped organ in the abdomen that completes the process of digestion. It consists of the small and large intestines.
Intraepithelial (in-tra-eh-pih-THEEL-ee-ul): Within the layer of cells that forms the surface or lining of an organ.
Intrahepatic (in-tra-hep-AT-ik): Within the liver.
Intrahepatic bile duct (in-tra-hep-AT-ik): The bile duct that passes through and drains bile from the liver.
Intraoperative radiation therapy: Radiation treatment given during surgery. Also called IORT.
Intraperitoneal chemotherapy (IN-tra-per-i-to-NEE-al): Treatment in which anticancer drugs are put directly into the abdomen through a thin tube.
Intrathecal chemotherapy (in-tra-THEE-cal KEE-mo-THER-a-pee): Chemotherapy drugs infused into the thin space between the lining of the spinal cord and brain to treat or prevent cancers in the brain and spinal cord.
Intravenous (in-tra-VEE-nus): Injected in a vein. Also called IV.
Intravenous pyelogram (in-tra-VEE-nus PIE-el-o-gram): A series of x-rays of the kidneys and bladder. The x-rays are taken after a dye that shows up on x-ray film in injected into a vein. Also called IVP.
Intravenous pyelography (om-tra-VEE-nus py-LOG-ra-fee): X-ray study of the kidneys and urinary tract. Structures are made visible by the injection of a substance that blocks x-rays. Also called IVP.
Intravesical (in-tra-VES-ih-kal): Within the bladder.
Institutional Review Board (IRB) - An Institutional Review Board (IRB) is an objective, multidisciplinary group of individuals that reviews and approves or disapproves clinical trials for a medical institution. The Board is made up of doctors from different specialties, ethicists (often a chaplain), administrators, and members of the public. An IRB is required by the U.S. Food and Drug Administration (FDA) to ensure protection of the rights and welfare of patients who are enrolled in clinical trials.
Invasion: As related to cancer, the spread of cancer cells into healthy tissue adjacent to the tumor.
Invasive cancer: Cancer that has spread beyond the layer of tissue in which it developed. Invasive breast cancer is also called infiltrating cancer or infiltrating carcinoma.
Invasive cervical cancer: Cancer that has spread from the surface of the cervix to tissue deeper in the cervix or to other parts of the body.
IORT (intraoperative radiation therapy): Radiation treatment given during surgery.
Islet cell cancer (EYE-let): Cancer arising from cells in the islets of Langerhans.
Islets of Langerhans (EYE-lets of LANG-er-hanz): Hormone-producing cells in the pancreas.
IV (intravenous) (in-tra-VEE-nus): Injected in a vein.
IVP (intravenous pyelogram) (in-tra-VEE-nus PYE-el-o-gram): X-ray study of the kidneys, uterus, and urinary tract. Structures are made visible by the injection of a substance that blocks x-rays.
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Jaundice (JAWN-dis): A condition in which the skin and the whites of the eyes become yellow and the urine darkens. Jaundice occurs when the liver is not working properly or when a bile duct is blocked.
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Kaposi's sarcoma (KAP-o-seez-sar-KO-ma): A relatively rare type of cancer that develops on the skin of some elderly persons or those with a weak immune system, including those with acquired immune deficiency syndrome (AIDS).
Kidneys (KID-neez): A pair or organs in the abdomen that remove waste from the blood. The waste leaves the blood as urine.
Kidney cancer: Renal cell cancer (also called cancer of the kidney or renal adenocarcinoma) is a disease in which cancer (malignant) cells are found in certain tissues of the kidney. Renal cell cancer is one of the less common kinds of cancer. It occurs more often in men than in women.
Krukenberg tumor (KROO-ken-berg): A tumor of the ovary caused by the spread of stomach cancer.
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Laparoscopy (lap-a-ROS-ko-pee): A surgical procedure in which a lighted instrument shaped like a thin tube is inserted through a small incision in the abdomen. The doctor can look through the instrument and see inside the abdomen.
Laparotomy (lap-a-ROT-o-mee): An operation that allows the doctor to inspect the organs in the abdomen. Large cell carcinomas: A group of lung cancers in which the cells are large and look abnormal.
Laryngeal (lair-IN-jee-al): Having to do with the larynx.
Laryngectomee (lair-in-JEK-toe-mee): A person who has had his or her voice box removed.
Laryngectomy (lair-in-JEK-toe-mee): An operation to remove all or part of the larynx.
Laryngoscope (lair-IN-jo-skope): A flexible lighted tube used to examine the larynx.
Laryngoscopy (lair-in-GOS-ko-pee): Examination of the larynx with a mirror (indirect laryngoscopy) or with a laryngoscope (direct laryngoscopy).
Larynx (LAIR-inks): An organ in the throat used in breathing, swallowing, and talking. It is made of cartilage and is line by a mucous membrane similar to the lining of the mouth. Also called the "voice box."
Laser (LAY-zer): A powerful beam of light used in some types of surgery to cut or destroy tissue.
Lesion (LEE-zhun): An area of abnormal tissue change.
Leukemia (loo-KEE-mee-a): Cancer of the blood cells.
Leukocytes (LOO-ko-sites): Cells that help the body fight infections and other diseases. Also called white blood cells (WBCs).
Leukoplakia (loo-ko-PLAY-kee-a): A white spot or patch in the mouth
Li-Fraumeni Syndrome: A rare family predisposition to multiple cancers, caused by an alteration in the p53 tumor suppressor gene.
Ligation (lye-GAY-shun): The process of tying off blood vessels so that blood cannot flow to a part of the body or to a tumor.
Limb perfusion (per-FYOO-zhun): A chemotherapy technique that may be used when melanoma occurs on an arm or leg. The flow of blood to and from the limb is stopped for a while with a tourniquet, and anticancer drugs are put directly into the blood of the limb. This allows the patient to receive a high dose of drugs in the area where the melanoma occurred.
Liver: A large, glandular organ, located in the upper abdomen, that cleanses the blood and aids in digestion by secreting bile.
Liver scan: An image of the liver created on a computer screen or on film. For a liver scan, a radioactive substance is injected into a vein and travels through the bloodstream. It collects in the liver, especially in abnormal areas, and can be detected by the scanner.
Lobe: A portion of the liver, lung, breast, or brain.
Lobectomy (lo-BEK-to-mee): The removal of a lobe.
Lobular carcinoma in situ (LOB-yoo-lar-sin-O-ma in SY-too): Abnormal cells in the lobules of the breast. This condition seldom becomes invasive cancer. However, having lobular carcinoma in situ is a sign that the woman has an increased risk of developing breast cancer. Also called LCIS.
Lobule (LOB-yule): A small lobe.
Local: Reaching and affecting only the cells in a specific area.
Local therapy: Treatment that affects cells in the tumor and the area close to it.
Lower GI series: A series of x-rays of the colon and rectum that is taken after the patient is given a barium enema. (Barium is a white, chalky substance that outlines the colon and rectum on the x-ray.)
Lubricant (LOO-brih-kant): An oily or slippery substance. A vaginal lubricant may be helpful for women who feels pain during intercourse because of vaginal dryness.
Lumbar puncture: The insertion of a needle into the lower part of the spinal column to collect cerebrospinal fluid or to give intrathecal chemotherapy. Also called a spinal tap.
Lumpectomy (lump-EK-toe-mee): Surgery to remove only the cancerous breast lump; usually followed by radiation therapy.
Luteinizing hormone-releasing hormone (LHRH) agonist (LOO-tin-eye-zing...AG-o-nist): A substance that closely resembles LHRH, which controls the production of sex hormones. However, LHRH agonists affect the body differently than does LHRH. LHRH agonists keep the testicles from producing hormones.
Lymph (limf): The almost colorless fluid that travels through the lymphatic system and carries cells that help fight infection and disease.
Lymph nodes: Small, bean-shaped organs located along the channels of the lymphatic system. The lymph nodes store special cells that can trap bacteria or cancer cells traveling through the body in lymph. Clusters of lymph nodes are found in the underarms, groin, neck, chest, and abdomen. Also called lymph glands.
Lymphangiogram (lim-FAN-jee-o-gram): An x-ray of the lymphatic system. A dye is injected to outline the lymphatic vessels and organs.
Lymphangiography (imf-an-jee-OG-ra-fee): X-ray study of lymph nodes and lymph vessels made visible by the injection of a special dye.
Lymphatic system (lim-FAT-ik): The tissues and organs that produce, store, and carry white blood cells that fight infection and disease. This system includes the bone marrow, spleen, thymus, and lymph nodes and a network of thin tubes that carry lymph and white blood cells. These tubes branch, like blood vessels, into all the tissues of the body.
Lymphedema (LIMF-eh-DEE-ma): A condition in which excess fluid collects in tissue and causes swelling. It may occur in the arm or leg after lymph vessels or lymph nodes in the underarm or groin are removed.
Lymphoma: Cancer that arises in cells of the lymphatic system.
Lymphocytes (LIMF-o-sites): White blood cells that fight infection and disease.
Lymphocytic (lim-fo-SIT-ik): Referring to lymphocytes, a type of white blood cell.
Lymphoid (LIM-foyd): Referring to lymphocytes, a type of white blood cell. Also refers to tissue in which lymphocytes develop.
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M proteins: Antibodies or parts of antibodies found in unusually large amounts in the blood or urine of multiple myeloma patients.
Magnetic resonance imaging (mag-NET-ik REZ-o-nan IM-a-jing): A procedure in which a magnet linked to a computer is used to create detailed pictures of areas inside the body. Also called MRI.
Maintenance therapy: Chemotherapy that is given to leukemia patients in remission to prevent a relapse.
Malignant (ma-LIG-nant): Cancerous; can invade nearby tissue and spread to other parts of the body.
Mammogram (MAM-o-gram): An x-ray of the breast. Mammography (mam-OG-ra-fee): The use of x-rays to create a picture of the breast.
Mastecomy (mas-TEK-to-mee): Surgery to remove the breast (or as much of the breast as possible).
Mediastinoscopy (MEE-dee-a-stin-AHS-ko-pee): A procedure in which the doctor inserts a tube into the chest to view the organs in the mediastinum. The tube is inserted through an incision above the breastbone.
Mediastinotomy (MEE-dee-a-stin-AH-toe-mee): A procedure in which the doctor inserts a tube into the chest to view the organs in the mediastinum. The tube is inserted through an incision next to the breastbone.
Mediastinum (mee-dee-a-STY-num): The area between the lungs. The organs in this area include the heart and its large veins and arteries, the trachea, the esophagus, the bronchi, and lymph nodes.
Medical oncologist (on-KOL-o-jist): A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment. For example, a radiation oncologist specializes in treating cancer with radiation.
Medulloblastoma (MED-yoo-lo-blas-TOE-ma): A type of brain tumor that recent research suggests develops from primitive (developing) nerve cells that normally do not remain in the body after birth. Medulloblastomas are sometimes called primitive neuroectodermal tumors.
Melanin (MEL-a-nin): A skin pigment (substance that gives the skin its color). Dark-skinned people have more melanin than light-skinned people.
Melanocytes (mel-AN-o-sites): Cells in the skin that produce and contain the pigment called melanin.
Melanoma: Cancer of the cells that produce pigment in the skin. Melanoma usually begins in a mole.
Membrane: A very thin layer of tissue that covers a surface.
Meninges (meh-NIN-jeez): The three membranes that cover the brain and spinal cord.
Meningioma (meh-nin-jee-O-ma): A type of brain tumor that develops in the meninges. Because these tumors grow very slowly, the brain may be able to adjust to their presence; meningiomas often grow quite large before they cause symptoms.
Menopause (MEN-o-pawz): The time of a woman's life when menstrual periods permanently stop. Also called "change of life."
Menstrual cycle (MEN-stroo-al): The hormone changes that lead up to a woman's having a period. For most women, one cycle takes 28 days.
Metastasize (meh-TAS-ta-size): To spread from one part of the body to another. When cancer cells metastasize and form secondary tumors, the cells in the metastatic tumor are like those in the original (primary) tumor.
Microcalcifications (MY-krow-kal-si-fi-KA-shunz): Tiny deposits of calcium in the breast that cannot be felt but can be detected on a mammogram. A cluster of these very small specks of calcium may indicate that cancer is present.
Mole: An area on the skin (usually dark in color) that contains a cluster of melanocytes.
Monoclonal antibodies (MON-o-KLO-nul AN-ti-BOD-eez): Substances that can locate and bind to cancer cells wherever they are in the body. They can be used alone, or they can be used to deliver drugs, toxins, or radioactive material directly to tumor cells.
Monocyte: A type of white blood cell.
Morphology: The science of the form and structure of organisms (plants, animals, and other forms of life).
MRI (magnetic resonance imaging): A procedure in which a magnet linked to a computer is used to create detailed pictures of areas inside the body.
Mucus: A thick fluid produced by the lining of some organs of the body.
Multiple myeloma (mye-eh-LO-ma): Cancer that affects plasma cells. The disease causes the growth of tumors in many bones, which can lead to bone pain and fractures. In addition, the disease often causes kidney problems and lowered resistance to infection.
Mutations: Changes in the way cells function or develop, caused by an inherited genetic defect or an environmental exposure. Such changes may lead to cancer.
Mycosis fungoides (my-KO-sis fun-GOY-deez): A type of non-Hodgkin's lymphoma that first appears on the skin. Also called cutaneous T-cell lymphoma.
Myelin (MYE-eh-lin): The fatty substance that covers and protects nerves.
Myelodysplastic syndrome (MYE-eh-lo-dis-PLAS-tik SIN-drome): See Preleukemia.
Myelogenous (mye-eh-LAH-jen-us): Referring to myelocytes, a type of white blood cell. Also called myeloid.
Myelogram (MYE-eh-lo-gram): An x-ray of the spinal cord and the bones of the spine.
Myeloid (MYE-eh-loyd): Referring to myelocytes, a type of white blood cell. Also called myelogenous.
Myometrium (my-o-MEE-tree-um): The muscular outer layer of the uterus.
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Neck dissection (dye-SEK-shun): Surgery to remove lymph nodes and other tissues in the neck.
Neoplasia (NEE-o-play-zha): Abnormal new growth of cells.
Neoplasm: A new growth of tissue. Can be referred to as benign or malignant.
Nephrectomy (nef-REK-to-mee): Surgery to remove the kidney. Radical nephrectomy removes the kidney, the adrenal gland, nearby lymph nodes, and other surrounding tissue. Simple nephrectomy removes just the affected kidney. Partial nephrectomy removes the tumor, but not the entire kidney.
Nephrotomogram (nef-ro-TOE-mo-gram): A series of special x-rays of the kidneys. The x- rays are taken from different angles. They show the kidneys clearly, without the shadows of the organs around them.
Neurologist (noo-ROL-o-jist): A doctor who specializes in the diagnosis and treatment of disorders of the nervous system.
Neuroma (noo-RO-ma): A tumor that arises in nerve cells.
Neurosurgeon (NOO-ro-SER-jun): A doctor who specializes in surgery on the brain and other parts of the nervous system.
Neutrophil (NOO-tro-fil): A type of white blood cell.
Nevus (NEE-vus): The medical term for a spot on the skin, such as a mole. A mole is a cluster of melanocytes that usually appears as a dark spot on the skin. The plural of nevus is nevi (NEE-vye).
Nitrosoureas (nye-TRO-so-yoo-REE-ahz): A group of anticancer drugs that can cross the blood-brain barrier. Carmustine (BCNU) and lomustine (CCNU) are nitrosoureas.
Nonmelanoma skin cancer: Skin cancer that does not involve melanocytes. Basal cell cancer and squamous cell cancer are nonmelanoma skin cancers.
Nonseminoma (non-sem-i-NO-ma): A classification of testicular cancers that arise in specialized sex cells called germ cells. Nonseminomas include embryonal carcinoma, teratoma, choriocarcinoma, and yolk sac tumor.
Nonsmall cell lung cancer: A form of lung cancer associated with smoking, exposure to environmental tobacco smoke, or exposure to radon. Nonsmall cell lung cancer is classified as squamous cell carcinoma, adenocarcinoma, and large cell carcinoma depending on what type of cells are in the cancer.
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Oat cell cancer: A type of lung cancer in which the cells look like oats. Also called small cell lung cancer.
Oligodendroglioma (OL-ih-go-den-dro-glee-O-ma): A rare, slow growing type of brain tumor that occurs in the cells that produce myelin, the fatty covering that protects nerves.
Ommaya reservoir (o-MYE-a REZ-er-vwahr): A device implanted under the scalp and used to deliver anticancer drugs to the fluid surrounding the brain and spinal cord.
Oncogene: The part of the cell that normally directs cell growth, but which can also promote or allow the uncontrolled growth of cancer if damaged (mutated) by an environmental exposure to carcinogens, or damaged or missing because of an inherited defect.
Oncologist (on-KOL-o-jist): A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment. For example, a radiation oncologist specializes in treating cancer with radiation.
Oncology: The study of tumors encompassing the physical, chemical, and biologic properties.
Oophorectomy (oo-for-EK-to-mee): The removal of one or both ovaries.
Ophthalmoscope (off-THAL-mo-skope): A lighted instrument used to examine the inside of the eye, including the retina and the optic nerve.
Optic nerve: The nerve that carries messages from the retina to the brain.
Oral surgeon: A dentist with special training in surgery of the mouth and jaw.
Orchiectomy (or-kee-EK-to-mee): Surgery to remove the testicles.
Organisms: Plants, animals, and other forms of life that are made up of complex and interconnected systems of cells and tissue.
Oropharynx (or-o-FAIR-inks): The area of the throat at the back of the mouth.
Osteosarcoma (OSS-tee-o-sar-KO-ma): A cancer of the bone that is most common in children. Also called osteogenic sarcoma.
Ostomy (AHS-toe-mee): An operation to create an opening from an area inside the body to the outside. See Colostomy.
Otolaryngologist (AH-toe-lar-in-GOL-o-jist): A doctor who specializes in treating diseases of the ear, nose, and throat.
Ovaries (O-var-eez): The pair of female reproductive glands in which the ova, or eggs, are formed. The ovaries are located in the lower abdomen, one on each side of the uterus.
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p53: A gene in the cell that normally inhibits the growth of tumors, which can prevent or slow the spread of cancer.
Palate (PAL-et): The roof of the mouth. The front portion is bony (hard palate), and the back portion is muscular (soft palate).
Palliative treatment: Treatment that does not alter the course of a disease, but improves the quality of life.
Palpation (pal-PAY-shun): A technique in which a doctor presses on the surface of the body to feel the organs or tissues underneath.
Pancreas: A gland located in the abdomen. It makes pancreatic juices, and it produces several hormones, including insulin. The pancreas is surrounded by the stomach, intestines, and other organs.
Pancreatectomy (pan-kree-a-TEK-to-mee): Surgery to remove the pancreas. In a total pancreatectomy, the duodenum, common bile duct, gallbladder, spleen, and nearby lymph nodes also are removed.
Pancreatic juices: Fluids made by the pancreas. Pancreatic juices contain proteins called enzymes that aid in digestion.
Papillary tumor (PAP-i-lar-ee): A tumor shaped like a small mushroom with its stem attached to the inner lining of the bladder.
Papilledema (pap-il-eh-DEE-ma): Swelling around the optic nerve, usually due to pressure on the nerve by a tumor.
Pap test: Microscopic examination of cells collected from the cervix. It is used to detect changes that may be cancer or may lead to cancer, and it can show noncancerous conditions, such as infection or inflammation. Also called Pap smear.
Paralysis (pa-RAL-ih-sis): Loss of ability to move all or part of the body.
Paraneoplastic syndrome (pair-a-nee-o-PLAS-tik): A group of symptoms that may develop when substances released by some cancer cells disrupt the normal function of surrounding cells and tissue. Such symptoms do not necessarily mean that the cancer has spread beyond the original site.
Pathologist (pa-THOL-o-jist): A doctor who identifies diseases by studying cells and tissues under a microscope.
Pediatric (pee-dee-AT-rik): Pertaining to children.
Pelvis: The lower part of the abdomen, located between the hip bones.
Percutaneous transhepatic cholangiography (per-kyoo-TAN-ee-us trans-heh-PAT-ik ko-LAN-jee-AH-gra-fee): A test sometimes used to help diagnose cancer of the pancreas. During this test, a thin needle is put into the liver. Dye is injected into the bile ducts in the liver so that blockages can be seen on x-rays.
Perfusion: The process of flooding fluid through the artery to saturate the surrounding tissue. In regional perfusion, a specific area of the body (usually an arm or a leg) is targeted and high doses of anticancer drugs are flooded through the artery to reach the surrounding tissue and kill as many cancer cells as possible. Such a procedure is performed in cases where the cancer is not thought to have spread past a localized area.
Perineal prostatectomy (pe-ri-NEE-al): Surgery to remove the prostate through an incision made between the scrotum and the anus.
Peripheral blood stem cell transplantation (per-IF-er-al): A procedure that is similar to bone marrow transplantation. Doctors remove healthy immature cells (stem cells) from a patient's blood and store them before the patient receives high-dose chemotherapy and possibly radiation therapy to destroy the leukemia cells. The stem cells are then returned to the patient, where they can produce new blood cells to replace cells destroyed by the treatment.
Peripheral stem cell support (per-IF-er-ul): A method of replacing blood-forming cells destroyed by cancer treatment. Certain cells (stem cells) in the blood that are similar to those in the bone marrow are removed from the patient's blood before treatment. The cells are given back to the patient after treatment.
Peristalsis (pair-ih-STAL-sis): The rippling motion of muscles in the digestive tract. In the stomach, this motion mixes food with gastric juices, turning it into a thin liquid.
Peritoneal cavity: The lower part of the abdomen that contains the intestines (the last part of the digestive tract), the stomach, and the liver. It is bound by thin membranes.
Peritoneum (PAIR-i-to-NEE-um): The large membrane that lines the abdominal cavity.
Pernicious anemia (per-NISH-us a-NEE-mee-a): A blood disorder caused by a lack of vitamin B12. Patients who have this disorder do not produce the substance in the stomach that allows the body to absorb vitamin B12.
Personalized Medicine: A form of medicine that uses information about a person's genes, proteins, and environment to prevent, diagnose, and treat disease.
Petechiae (peh-TEE-kee-a): Tiny red spots under the skin; often a symptom of leukemia.
Pharmacogenomics: The study of variations of DNA and RNA characteristics as related
to drug response; is one of the most exciting areas of personalized medicine today.
Pharynx (FAIR-inks): The hollow tube about 5 inches long that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes to the stomach).
Photodynamic therapy (fo-to-dy-NAM-ik): Treatment that destroys cancer cells with lasers and drugs that become active when exposed to light.
Pigment: A substance that gives color to tissue. Pigments are responsible for the color of skin, eyes, and hair.
Pineal gland (PIN-ee-al): A small gland located in the cerebrum.
Pineal region tumors: Types of brain tumors that occur in or around the pineal gland, a tiny organ near the center of the brain. The pineal region is very difficult to reach, therefore these tumors often cannot be removed.
Pineoblastoma (PIN-ee-o-blas-TOE-ma): A fast growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.
Pineocytoma (PIN-ee-o-sye-TOE-ma): A slow growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.
Pituitary gland (pih-TOO-ih-tair-ee): The main endocrine gland; it produces hormones that control other glands and many body functions, especially growth.
Plasma: The liquid part of the blood.
Plasma cells: Special white blood cells that produce antibodies.
Plasmacytoma: A tumor that is made up of cancerous plasma cells.
Plasmapheresis (plas-ma-fer-EE-sis): The process of removing certain proteins from the blood. Plasmapheresis can be used to remove excess antibodies from the blood of multiple myeloma patients.
Plastic surgeon: A surgeon who specializes in reducing scarring or disfigurement that may occur as a result of accidents, birth defects, or treatment for diseases (such as melanoma).
Platelets (PLAYT-lets): Blood cells that help clots form to help control bleeding. Also called thrombocytes.
Pleura (PLOOR-a): The thin covering that protects and cushions the lungs. The pleura is made up of two layers of tissue that are separated by a small amount of fluid.
Pleural cavity: A space enclosed by the pleura, thin tissue covering the lungs and lining the interior wall of the chest cavity. It is bound by serous membranes.
Pneumatic larynx (noo-MAT-ik): A device that uses air to produce sound to help a laryngectomee talk.
Pneumonectomy (noo-mo-NEK-to-mee): An operation to remove an entire lung.
Pneumonia (noo-MONE-ya): An infection that occurs when fluid and cells collect in the lung.
Polyp (POL-ip): A mass of tissue that projects into the colon.
Positron emission tomography scan: For this type of scan, a person is given a substance that reacts with tissues in the body to release protons (parts of an atom). Through measuring the different amounts of protons released by healthy and cancerous tissues, a computer creates a picture of the inside of the body. Also called PET scan.
Postremission therapy: Chemotherapy to kill leukemia cells that survive after remission induction therapy.
Precancerous (pre-KAN-ser-us): A term used to describe a condition that may or is likely to become cancer.
Precancerous polyps: Growths in the colon that often become cancerous.
Prednisone: A drug often given to multiple myeloma patients along with one or more anticancer drugs. Prednisone appears to act together with anticancer drugs in helping to control the effects of the disease on the body.
Preleukemia (PREE-loo-KEE-mee-a): A condition in which the bone marrow does not function normally. It does not produce enough blood cells. This condition may progress and become acute leukemia. Preleukemia also is called myelodysplastic syndrome or smoldering leukemia.
Primitive neuroectodermal tumors (NOO-ro-ek-toe-DER-mul): A type of brain tumor that recent research suggests develops from primitive (developing) nerve cells that normally do not remain in the body after birth. Primitive neuroectodermal tumors are often called medulloblastomas.
Proctoscopy (prok-TOS-ko-pee): An examination of the rectum and the lower end of the colon using a thin lighted instrument called a sigmoidoscope.
Proctosigmoidoscopy (PROK-toe-sig-moid-OSS-ko-pee): An examination of the rectum and the lower part of the colon using a thin, lighted instrument called a sigmoidoscope.
Progesterone (pro-JES-ter-own): A female hormone.
Prognosis (prog-NO-sis): The probable outcome or course of a disease; the chance of recovery.
Prophylactic cranial irradiation (pro-fi-LAK-tik KRAY-nee-ul ir-ray-dee-AY-shun): Radiation therapy to the head to prevent cancer from spreading to the brain.
Prostatectomy (pros-ta-TEK-to-mee): An operation to remove part or all of the prostate.
Prostate gland (PROS-tate): A gland in the male reproductive system just below the bladder. It surrounds part of the urethra, the canal that empties the bladder. It produces a fluid that forms part of semen.
Prostate-specific antigen (PSA): A protein whose level in the blood goes up in some men who have prostate cancer or benign prostatic hyperplasia.
Prostatic acid phosphatase (FOS-fa-tase): An enzyme produced by the prostate. Its level in the blood goes up in some men who have prostate cancer. Also called PAP.
Prosthesis (pros-THEE-sis): An artificial replacement for a body part.
Prosthodontist (pros-tho-DON-tist): A dentist with special training in making replacements for missing teeth or other structures of the oral cavity to restore the patient's appearance, comfort, and/or health.
Proteins (PRO-teenz): Substances that are essential to the body's structure and proper functioning.
PTC (percutaneous transhepatic cholangiography) (per-kyoo-TAN-ee-us trans-heh-PAT-ik ko-LAN-jee-AH-gra-fee): A test sometimes used to help diagnose cancer of the pancreas. During this test, a thin needle is put into the liver. Dye is injected into the bile ducts in the liver so that blockages can be seen on x-rays.
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Radiation fibrosis (ray-dee-AY-shun-fye-BRO-sis): The formation of scar tissue as a result of radiation therapy to the lung.
Radiation therapy (ray-dee-AY-shun): Treatment with high-energy rays to kill cancer cells.
Radiation oncologist (ray-dee-AY-shun on-KOL-o-jist): A doctor who specializes in using radiation to treat cancer.
Radiation therapy (ray-dee-AY-shun): Treatment with high-energy rays (such as x-rays) to kill cancer cells. The radiation may come from outside the body (external radiation) or from radioactive materials placed directly in the tumor (implant radiation). Also called radiotherapy.
Radical cystectomy (RAD-i-kal sis-TEK-to-mee): Surgery to remove the bladder as well as nearby tissues and organs.
Radical prostatectomy: Surgery to remove the entire prostate. The two types of radical prostatectomy are retropubic prostatectomy and perineal prostatectomy.
Radioactive (RAY-dee-o-AK-tiv): Giving off radiatiion.
Radiologist: A doctor who specializes in creating and interpreting pictures of areas inside the body. The pictures are produced with x-rays, sound waves, or other types of energy.
Radionuclide scanning: An exam that produces pictures (scans) of internal parts of the body. The patient is given an injection or swallows a small amount of radioactive material. A machine called a scanner then measures the radioactivity in certain organs.
Radiosensitizers: Drugs that make cells more sensitive to radiation.
Radon (RAY-don): A radioactive gas that is released by uranium, a substance found in soil and rock. When too much radon is breathed in, it can damage lung cells and lead to lung cancer.
Rectum: The last 8 to 10 inches of the large intestine. The rectum stores solid waste until it leases the body through the anus.
Recur: To occur again. Recurrence is the reappearance of cancer cells at the same site or in another location.
Red blood cells: Cells that carry oxygen to all parts of the body. Also called erythrocytes.
Reed-Sternberg cell: A type of cell that appears in patients with Hodgkin's disease. The number of these cells increases as the disease advances.
Reflux: The term used when liquid backs up into the esophagus from the stomach.
Regional chemotherapy: Treatment with anticancer drugs that affects mainly the cells in the treated area.
Relapse: The return of signs and symptoms of a disease after a period of improvement.
Remission: Disappearance of the signs and symptoms of cancer. When this happens, the disease is said to be "in remission." A remission can be temporary or permanent.
Remission induction therapy: The initial chemotherapy a patient with acute leukemia receives to bring about a remission.
Renal capsule: The fibrous connective tissue that surrounds each kidney.
Renal cell cancer: Cancer that develops in the lining of the renal tubules, which filter the blood and produce urine.
Renal pelvis: The area at the center of the kidney. Urine collects here and is funneled into the ureter.
Reproductive cells: Egg and sperm cells. Each mature reproductive cell carries a single set of 23 chromosomes.
Reproductive system: The group of organs and glands involved with having a child. In women, these are the uterus (womb), the fallopian tubes, the ovaries, and the vagina (birth canal). The reproductive system in men includes the testes, the prostate, and the penis.
Resection (ree-SEK-shun): Surgical removal of part of an organ.
Respiratory system (RES-pi-ra-tor-ee): The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs.
Respiratory therapy (RES-pi-ra-tor-ee): Exercises and treatments that help patients recover lung function after surgery.
Retinoblastoma: An eye cancer caused by the loss of both gene copies of the tumor- suppressor gene RB; the inherited form typically occurs in childhood, because one gene is missing from the time of birth.
Retropubic prostatectomy (re-tro-PYOO-bik): Surgical removal of the prostate through an incision in the abdomen.
Risk factor: Something that increases the chance of developing a disease.
RNA (ribonucleic acid): One of the two nucleic acids found in all cells. The other is DNA (deoxyribonucleic acid). RNA transfers genetic information from DNA to proteins produced by the cell.
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Salivary glands (SAL-i-vair-ee): Glands in the mouth that produce saliva.
Salpingo-oophorectomy (sal-PING-o-OO-for-EK-to-mee): Surgical removal of the fallopian tubes and ovaries.
Sarcoma (sar-KO-ma): A malignant tumor that begins in connective and supportive tissue.
Scans: Pictures of organs in the body. Scans often used in diagnosing, staging, and monitoring patients include liver scans, bone scans, and computed tomography (CT) or computed axial tomography (CAT) scans. In liver scanning and bone scanning, radioactive substances that are injected into the bloodstream collect in these organs. A scanner that detects the radiation is used to create pictures. In CT scanning, an x-ray machine linked to a computer is used to produce detailed pictures of organs inside the body.
Schiller test (SHIL-er): A test in which iodine is applied to the cervix. The iodine colors healthy cells brown; abnormal cells remain unstained, usually appearing white or yellow.
Schwannoma (shwah-NO-ma): A type of benign brain tumor that begins in the Schwann cells, which produce the myelin that protects the acoustic nerve - the nerve of hearing.
Screening: Checking for disease when there are no symptoms.
Scrotum (SKRO-tum): The external pouch of skin that contains the testicles.
Sebum (SEE-bum): An oily substance produced by certain glands in the skin.
Seizures (SEE-zhurz): Convulsions; sudden, involuntary movements of the muscles.
Semen: The fluid that is released through the penis during orgasm. Semen is made up of sperm from the testicles and fluid from the prostate and other sex glands.
Seminal vesicles (SEM-in-al VES-i-kulz): Glands that help produce semen.
Seminoma (sem-in-O-ma): A type of testicular cancer that arises from sex cells, or germ cells, at a very early stage in their development.
Shunt: A catheter (tube) that carries cerebrospinal fluid from a ventricle in the brain to another area of the body.
Side effects: Problems that occur when treatment affects healthy cells. Common side effects of cancer treatment are fatigue, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.
Sigmoidoscope (sig-MOY-da-skope): An instrument used to view the inside of the colon.
Sigmoidoscopy (sig-moid-OSS-ko-pee): A procedure in which the doctor looks inside the rectum and the lower part of the colon (sigmoid colon) through a lighted tube. The doctor may collect samples of tissue or cells for closer examination. Also called proctosigmoidoscopy.
Skin graft: Skin that is moved from one part of the body to another.
Small cell lung cancer: A type of lung cancer in which the cells are small and round. Also called oat cell lung cancer.
Small intestine: The part of the digestive tract that is located between the stomach and the large intestine.
Smoldering leukemia: See Preleukemia.
Soft tissue sarcoma: A sarcoma that begins in the muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.
Somatic cells: All the body cells except the reproductive cells.
Somatic mutations: See mutation.
Speech pathologist: A specialist who evaluates and treats people with communication and swallowing problems. Also called a speech therapist.
Speculum (SPEK-yoo-lum): An instrument used to widen the opening of the vagina so that the cervix is more easily visible.
Sperm banking: Freezing sperm before cancer treatment for use in the future. This procedure can allow men to father children after loss of fertility.
SPF (Sun protection factor): A scale for rating sunscreens. Sunscreens with an SPF of 15 or higher provide the best protection from the sun's harmful rays. SPF stands for Sun Protection Factor.
Spinal tap: A test in which a fluid sample is removed from the spinal column with a thin needle. Also called a lumbar puncture.
Spleen: An organ that produces lymphocytes, filters the blood, stores blood cells, and destroys those that are aging. It is located on the left side of the abdomen near the stomach.
Splenectomy (splen-EK-toe-mee): An operation to remove the spleen.
Sputum (SPYOO-tum): Mucus from the lungs.
Squamous cell carcinoma (SKWAY-mus): Cancer that begins in squamous cells, which are thin, flat cells resembling fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts.
Squamous cells (SKWAY-mus): Flat cells that look like fish scales; they make up most of the epidermis, the outer layer of the skin.
Squamous intraepithelial lesion (SKWAY-mus in-tra-eh-pih-THEEL-ee-ul LEE-zhun): A general term for the abnormal growth of squamous cells on the surface of the cervix. The changes in the cells are described as low grade or high grade, depending on how much of the cervix is affected and how abnormal the cells are. Also called SIL.
Stage: The extent of a cancer, especially whether the disease has spread from the original site to other parts of the body.
Staging: Doing exams and tests to learn the extent of the cancer, especially whether it has spread from its original site to other parts of the body.
Stem cells: The cells from which all blood cells develop.
Stereotaxis (stair-ee-o-TAK-sis): Use of a computer and scanning devices to create three- dimensional pictures. This method can be used to direct a biopsy, external radiation, or the insertion of radiation implants.
Sterile: The inability to produce children.
Steroids (STEH-roidz): Drugs used to relieve swelling and inflammation.
Stoma: An opening in the abdominal wall; also called an ostomy or urostomy.
Stool: The waste matter discharged in a bowel movement; feces.
Stool test: A test to check for hidden blood in the bowel movement.
Subglottis (SUB-glot-is): The lowest part of the larynx; the area from just below the vocal cords down to the top of the trachea.
Sun Protection Factor (SPF): A scale for rating sunscreens. Sunscreens with an SPF of 15 or higher provide the best protection from the sun's harmful rays.
Sunscreen: A substance that blocks the effect of the sun's harmful rays. Using lotions or creams that contain sunscreens can protect the skin from damage that may lead to cancer.
Supportive care: Treatment given to prevent, control, or relieve complications and side effects and to improve the patient's comfort and quality of life.
Supraglottis (SOOP-ra-GLOT-is): The upper part of the larynx, including the epiglottis; the area above the vocal cords.
Surgery: A procedure to remove or repair a part of the body or to find out if disease is present.
Systemic (sis-TEM-ik): Reaching and affecting cells all over the body.
Systemic therapy (sis-TEM-ik): Treatment that uses substances that travel through the bloodstream, reaching and affecting cancer cells all over the body.
Systemic treatment (sis-TEM-ik): Treatment using substances that travel through the bloodstream, reaching and affecting cancer cells all over the body.
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Targeted Therapy: Is the name for anticancer treatments that interfere with how a cancer grows and spreads when a very specific abnormality is present.
T-cell lymphoma (lim-FO-ma): A cancer of the immune system that appears in the skin; also called mycosis fungoides.
Testicles (TES-ti-kuls): The two egg-shaped glands that produce sperm and male hormones.
Testosterone (tes-TOS-ter-own): A male sex hormone.
Thermography (ther-MOG-ra-fee): A test to measure and display heat patterns of tissues near the surface of the breast. Abnormal tissue generally is warmer than healthy tissue. This technique is under study; its value in detecting breast cancer has not been proven.
Thoracentesis (thor-a-sen-TEE-sis): Removal of fluid in the pleura through a needle.
Thoracic (thor-ASS-ik): Pertaining to the chest.
Thoracotomy (thor-a-KOT-o-mee): An operation to open the chest.
Thrombocytes (THROM-bo-sites): See Platelets.
Thrombophlebitis (throm-bo-fleh-BYE-tis): Inflammation of a vein that occurs when a blood clot forms.
Thymus: An organ in which lymphocytes mature and multiply. It lies behind the breastbone.
Tissue (TISH-oo): A group or layer of cells that together perform specific functions.
Tonsils: Small masses of lymphatic tissue on either side of the throat.
Topical chemotherapy (kee-mo-THER-a-pee): Treatment with anticancer drugs in a lotion or cream.
Total pancreatectomy (pan-cree-a-TEK-to-mee): Surgery to remove the entire pancreas.
Toxins: Poisons produced by certain animals, plants, or bacteria.
Trachea (TRAY-kee-a): The airway that leads from the larynx to the lungs. Also called the windpipe.
Tracheoesophageal puncture (TRAY-kee-o-eh-SOF-a-JEE-al PUNK-chur): A small opening made by a surgeon between the esophagus and the trachea. A valve keeps food out of the trachea but lets air into the esophagus for esophageal speech.
Tracheostomy (TRAY-kee-AHS-toe-mee): Surgery to create an opening (stoma) into the windpipe. The opening itself may also be called a tracheostomy.
Tracheostomy button (TRAY-kee-AHS-toe-mee): A _- to 1-1/2-inch-long plastic tube placed in the stoma to keep it open.
Tracheostomy tube (TRAY-kee-AHS-toe-mee): A 2- to 3-inch-long metal or plastic tube that keeps the stoma and trachea open. Also called a trach ("trake") tube.
Transformation: The change that a normal cell undergoes as it becomes malignant.
Transfusion (trans-FYOO-zhun): The transfer of blood or blood products from one person to another. Transitional cell carcinoma: Cancer that develops in the lining of the renal pelvis. This type of cancer also occurs in the ureter and the bladder.
Transitional cells: Cells lining some organs.
Transplantation (trans-plan-TAY-shun): The replacement of an organ with one from another person.
Transrectal ultrasound: The use of sound waves to detect cancer. An instrument is inserted into the rectum. Waves bounce off the prostate and the pattern of the echoes produced is converted into a picture by a computer.
Transurethral resection (TRANZ-yoo-REE-thral ree-SEK-shun): Surgery performed with a special instrument inserted through the urethra. Also called TUR.
Transurethral resection of the prostate (TRANZ-yoo-REE-thral): The use of an instrument inserted through the penis to remove tissue from the prostate. Also called TUR or TURP.
Transvaginal ultrasound: Sound waves sent out by a probe inserted in the vagina. The waves bounce off the ovaries, and a computer uses the echoes to create a picture called a sonogram. Also called TVS.
Tumor (TOO-mer): An abnormal mass of tissue that results from excessive cell division. Tumors perform no useful body function. They may either be benign (not cancerous) or malignant (cancerous).
Tumor debulking: Surgically removing as much of the tumor as possible.
Tumor marker: A substance in blood or other body fluids that may suggest that a person has cancer.
Tumor necrosis factor (ne-KRO-sis): A type of biological response modifier (a substance that can improve the body's natural response to disease). Scientists are still learning how this substance causes cancer cells to die.
Tumor-suppressor gene: Genes in the body that can suppress or block the development of cancer.
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Ulcerative colitis: A disease that causes long-term inflammation of the lining of the colon.
Ultrasonography: A test in which sound waves (called ultrasound) are bounced off tissues and the echoes are converted into a picture (sonogram).
Ultrasound: A test that bounces sound waves off tissues and internal organs and changes the echoes into pictures (sonograms). Tissues of different densities reflect sound waves differently.
Ultraviolet (UV) radiation (ul-tra-VYE-o-let ray-dee-AY-shun): Invisible rays that are part of the energy that comes from the sun. UV radiation can burn the skin and cause melanoma and other types of skin cancer. UV radiation that reaches the earth's surface is made up of two types of rays, called UVA and UVB rays. UVB rays are more likely than UVA rays to cause sunburn, but UVA rays pass further into the skin. Scientists have long thought that UVB radiation can cause melanoma and other types of skin cancer. They now think that UVA radiation also may add to skin damage that can lead to cancer. For this reason, skin specialists recommend that people use sunscreens that block or absorb both kinds of UV radiation.
Upper GI series: A series of x-rays of the upper digestive system that are taken after a person drinks a barium solution, which outlines the digestive organs on the x-rays.
Ureter (yoo-REE-ter): The tube that carries urine from the kidney to the bladder.
Urethra (yoo-REE-thra): The tube that empties urine from the bladder. Urinalysis: A test that determines the content of the urine.
Urinary tract (YUR-in-air-ee): The organs of the body that produce and discharge urine. These include the kidneys, ureters, bladder, and urethra.
Urine (YUR-in): Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.
Urologist (yoo-RAHL-o-jist): A doctor who specializes in diseases of the urinary organs in females and the urinary and sex organs in males.
Urostomy (yoo-RAHS-toe-mee): An operation to create an opening from inside the body to the outside, making a new way to pass urine.
Uterus (YOO-ter-us): The small, hollow, pear-shaped organ in a woman's pelvis. This is the organ in which an unborn child develops. Also called the womb.
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Vagina (vah-JYE-na): The muscular canal extending from the uterus to the exterior of the body.
Vasectomy (vas-EK-to-mee): An operation to cut or tie off the two tubes that carry sperm out of the testicles.
Ventricles (VEN-trih-kulz): Four connected cavities (hollow spaces) in the brain.
Vinyl chloride (VYE-nil KLO-ride): A substance used in manufacturing plastics. It is linked to liver cancer.
Viruses (VYE-rus-ez): Small living particles that can infect cells and change how the cells function. Infection with a virus can cause a person to develop symptoms. The disease and symptoms that are caused depend on the type of virus and the type of cells that are infected.
Vital: Necessary to maintain life. Breathing is a vital function.
Vocal cords: Two small bands of muscle within the larynx. They close to prevent food from getting into the lungs, and they vibrate to produce the voice.
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Wart: A raised growth on the surface of the skin or other organ.
Whipple procedure: A type of surgery used to treat pancreatic cancer. The surgeon removes the head of the pancreas, the duodenum, a portion of the stomach, and other nearby tissues.
White blood cells: Cells that help the body fight infection and disease. These cells begin their development in the bone marrow and then travel to other parts of the body.
Wilms' tumor: A kidney cancer that occurs in children, usually before the age of five.
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Xerogram: An x-ray of soft tissue.
Xeroradiography (ZEE-roe-ray-dee-OG-ra-fee): A type of mammography in which a picture of the breast is recorded on paper rather than on film.
X-ray: High-energy radiation used in low doses to diagnose diseases and in high doses to treat cancer.
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