Cancer Information -- Cancer Dictionary

Cancer Information

Cancer Dictionary

L-377,202: A substance that is being studied in the treatment of cancer.

L-778,123: An anticancer drug that belongs to the family of drugs called enzyme inhibitors. It may inhibit the transformation of normal cells into cancer cells.

lactose intolerance: The inability to digest or absorb lactose, a type of sugar found in milk and other dairy products.

lamivudine: A drug used to treat infection caused by viruses.

laparoscopic-assisted colectomy: Surgery done with the aid of a laparoscope (a thin, lighted tube) to remove part or all of the colon through small incisions made in the wall of the abdomen.

laparoscopy (lap-a-RAHS-ko-pee): The insertion of a thin, lighted tube (called a laparoscope) through the abdominal wall to inspect the inside of the abdomen and remove tissue samples.

laparotomy (lap-a-RAH-toe-mee): A surgical incision made in the wall of the abdomen.

large cell carcinomas (kar-sin-O-mas): A group of lung cancers in which the cells are large and look abnormal when viewed under a microscope.

laryngeal (lair-IN-jee-al): Having to do with the larynx.

laryngectomee (lair-in-JEK-toe-mee): A person whose larynx (voice box) has been removed.

laryngectomy (lair-in-JEK-toe-mee): An operation to remove all or part of the larynx (voice box).

laryngoscope (lair-IN-jo-skope): A thin, lighted tube used to examine the larynx (voice box).

laryngoscopy (lair-in-GOS-ko-pee): Examination of the larynx (voice box) with a mirror (indirect laryngoscopy) or with a laryngoscope (direct laryngoscopy).

larynx (LAIR-inks): The area of the throat containing the vocal cords and used for breathing, swallowing and talking. Also called the voice box.

laser (LAY-zer): A device that concentrates light into an intense, narrow beam used to cut or destroy tissue. It is used in microsurgery, photodynamic therapy and for a variety of diagnostic purposes.

laser therapy: The use of an intensely powerful beam of light to kill cancer cells.

leflunomide: An anticancer drug that works by inhibiting a cancer cell growth factor. Also called SU101.

leiomyoma: A benign smooth-muscle tumor, usually in the uterus or gastrointestinal tract. Also called fibroid.

leiomyosarcoma: A tumor of the muscles in the uterus, abdomen, or pelvis.

lepirudin: A drug that inhibits blood clotting; it is being studied in cancer treatment.

leptomeningeal cancer: A tumor that involves the tissues that cover the brain and spinal cord.

leptomeningeal metastases: Cancer that has spread from the original (primary) tumor to the tissues that cover the brain and spinal cord.

leridistim: A substance that is being studied for its ability to increase numbers of white blood cells in people undergoing chemotherapy. It belongs to the family of drugs called colony-stimulating factors.

lerisetron: A drug that prevents or reduces nausea and vomiting.

lesion (LEE-zhun): An area of abnormal tissue change.

letrozole: An anticancer drug that belongs to the family of drugs called nonsteroidal aromatase inhibitors. Letrozole is used to decrease estrogen production and suppress the growth of estrogen-dependent tumors.

leucovorin: A drug used to protect normal cells from high doses of the anticancer drug methotrexate. It is also used to increase the antitumor effects of fluorouracil and tegafur-uracil, an oral treatment alternative to intravenous fluorouracil.

leukapheresis: Removal of the blood to collect specific blood cells; the remaining blood is returned to the body.

leukemia (loo-KEE-mee-a): Cancer of blood-forming tissue. See also acute lymphoblastic leukemia, acute myeloid leukemia.

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 patch that may develop on mucous membranes such as the cheek, gums, or tongue and may become cancerous.

leuprolide: A drug that belongs to a family of drugs called gonadotropin-releasing hormone analogues. It is used to block hormone production in the ovaries or testicles.

leuvectin: An agent that delivers the gene for interleukin-2 (IL-2) into cells to increase production of IL-2 by the cells.

levamisole: An antiparasitic drug that is also being studied in cancer therapy with fluorouracil.

levofloxacin: A substance used to treat bacterial infections. It belongs to the family of drugs called quinolone antibiotics.

LH-RH: Abbreviation for luteinizing hormone-releasing hormone, a hormone that controls the production of sex hormones in men and women.

Li-Fraumeni syndrome: A rare, inherited predisposition to multiple cancers, caused by an alteration in the p53 tumor suppressor gene.

liarozole: An anticancer drug that promotes differentiation by increasing the levels of retinoic acid within the tumor.

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 technique that may be used to deliver anticancer drugs directly to an arm or leg. The flow of blood to and from the limb is temporarily stopped with a tourniquet and anticancer drugs are put directly into the blood of the limb. This allows the person to receive a high dose of drugs in the area where the cancer occurred.

limited-stage small cell lung cancer: Cancer found in one lung and in nearby lymph nodes.

liothyronine sodium: A thyroid hormone. Also called triiodothyronine or T-3.

lipid: Fat.

liposarcoma: A rare cancer of the fat cells.

liposomal: A drug preparation that contains the active drug in very tiny fat particles. This fat-encapsulated drug is absorbed better and its distribution to the tumor site is improved.

lisofylline: A drug that may protect healthy cells from chemotherapy and radiation without inhibiting the effects of these therapies on tumor cells.

liver: A large, glandular organ located in the upper abdomen. The liver cleanses the blood and aids in digestion by secreting bile.

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

liver scan: An image of the liver created on a computer screen or on film. A radioactive substance is injected into a blood vessel and travels through the bloodstream. It collects in the liver, especially in abnormal areas and can be detected by the scanner.

LMB-1 immunotoxin: A toxic substance linked to an antibody that attaches to tumor cells and kills them.

LMB-2 immunotoxin: A toxic substance linked to an antibody that attaches to tumor cells and kills them.

LMB-7 immunotoxin: A toxic substance linked to an antibody that attaches to tumor cells and kills them.

LMB-9 immunotoxin: A toxic substance linked to an antibody that attaches to tumor cells and kills them.

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

lobe: A portion of an organ such as the liver, lung, breast, or brain.

lobectomy (lo-BEK-toe-mee): The removal of a lobe.

lobradimil: A substance that is being studied for its ability to help other drugs reach the brain. It belongs to the family of drugs called bradykinin agonists. Also called RMP-7.

lobular carcinoma in situ (LOB-yoo-lar kar-sin-O-ma in SYE-too): LCIS. Abnormal cells found in the lobules of the breast. This condition seldom becomes invasive cancer; however, having lobular carcinoma in situ increases one's risk of developing breast cancer in either breast.

lobule (LOB-yule): A small lobe or subdivision of a lobe.

local cancer: An invasive malignant cancer confined entirely to the organ where the cancer began.

local therapy: Treatment that affects cells in the tumor and the area close to it.

localized: Restricted to the site of origin, without evidence of spread.

localized gallbladder cancer: Cancer found only in the tissues that make up the wall of the gallbladder; it can be removed completely in an operation.

locally advanced cancer: Cancer that has spread only to nearby tissues or lymph nodes.

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

loperamide hydrochloride: An antidiarrheal drug.

losoxantrone: An anticancer drug that belongs to the family of drugs called antipyrazoles.

low-grade lymphomas: Lymphomas that tend to grow and spread slowly, including chronic lymphocytic lymphoma and follicular small cleaved cell lymphoma. Also called indolent lymphomas.

lower GI series: X-rays of the colon and rectum (lower gastrointestinal tract) that are taken after the person is given a barium enema.

LU 79553: An anticancer drug that kills cancer cells by affecting DNA synthesis.

LU-103793: An anticancer drug that reduces the risk of tumor cell growth and reproduction.

lubricants (LOO-brih-kants): Oily or slippery substances.

lumbar puncture: A procedure in which a needle is put into the lower part of the spinal column to collect cerebrospinal fluid or to give anticancer drugs intrathecally. Also called a spinal tap.

lumpectomy (lump-EK-toe-mee): Surgery to remove the tumor and a small amount of normal tissue around it.

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

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

luteinizing hormone-releasing hormone agonist (LOO-tin-eye-zing. . .AG-o-nist): LH-RH agonist. A drug that inhibits the secretion of sex hormones. In men, LH-RH agonist causes testosterone levels to fall. In women, LH-RH agonist causes the levels of estrogen and other sex hormones to fall.

lutetium texaphyrin: A substance that is being studied in photodynamic therapy. It belongs to the family of drugs called metallotexaphyrins.

LY231514: An anticancer drug that belongs to the family of drugs called enzyme inhibitors.

LY293111: A substance that is being studied as a treatment for cancer.

LY335979: A substance that is being studied for its ability to reverse resistance to chemotherapy.

LY353381 hydrochloride: A hormone substance used in the treatment of some types of cancer.

lycopene: A red pigment found in tomatoes and some fruits.

lymph (limf): The almost colorless fluid that travels through the lymphatic system and carries cells that help fight infection and disease.

lymph node: A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Also known as a lymph gland. Lymph nodes are spread out along lymphatic vessels and contain many lymphocytes, which filter the lymphatic fluid (lymph).

lymph node drainage: The flow of lymph from an area of tissue into a particular lymph node.

lymph node mapping: The use of dyes and radioactive substances to identify lymph nodes that contain tumor cells.

lymphadenectomy: A surgical procedure in which the lymph nodes are removed and examined to see whether they contain cancer. Also called lymph node dissection.

lymphangiogram (lim-FAN-jee-o-gram): X-rays of the lymphatic system. A dye is injected into a lymphatic vessel and travels throughout the lymphatic system. The dye outlines the lymphatic vessels and organs on the x-ray.

lymphangiography (lim-FAN-jee-AH-gra-fee): An x-ray study of the lymphatic system. A dye is injected into a lymphatic vessel and travels throughout the lymphatic system. The dye outlines the lymphatic vessels and organs on the x-ray.

lymphatic system (lim-FAT-ik): The tissues and organs that produce, store and carry white blood cells that fight infection and other diseases. 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 or treated with radiation.

lymphocyte (LIM-fo-site): A type of white blood cell that has a number of roles in the immune system. Some lymphocytes act as tumor-killing cells. Other lymphocytes produce antibodies or other substances that fight cancer, infection and other diseases. The main types of lymphocytes are T cells, B cells and natural killer (NK) cells.

lymphocytic (lim-fo-SIT-ik): Referring to lymphocytes, a type of white blood cell.

lymphography: An x-ray study of lymph nodes and lymphatic vessels made visible by the injection of a special dye.

lymphoid (LIM-foyd): Referring to lymphocytes, a type of white blood cell. Also refers to tissue in which lymphocytes develop.

lymphokine-activated killer cells: White blood cells that are stimulated in a laboratory to kill tumor cells. Also called LAK cells.

lymphoma (lim-FO-ma): Cancer that arises in cells of the lymphatic system.

lymphomatoid granulomatosis: Destructive growth of lymph cells, usually involving the lungs, skin, kidneys and central nervous system. Grades I and II are not considered cancerous, but grade III is considered a lymphoma.

lymphoproliferative disorders: Diseases in which cells of the lymphatic system grow excessively. These disorders are often treated like cancer.

Lynch syndrome: An inherited disorder in which affected individuals develop colon cancer, usually before the age of 60. Also called hereditary nonpolyposis colon cancer.

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This cancer dictionary is provided by the National Cancer Institute.