M protein(... PROH-teen) An antibody found in unusually large amounts in the blood or urine of people with multiple myeloma and other types of plasma cell tumors.
M-EDTAA substance being studied in the treatment of bacterial infections from catheters (flexible tubes used to deliver fluids into or take fluids from the…
M200A monoclonal antibody that is being studied in the treatment of some types of cancer.
ma huang(mah-hwong) A shrub native to China and India. The stems and roots are used in traditional medicine as a diuretic and for asthma, bronchitis, and cough.
macroglobulinemia(MA-kroh-GLAH-byoo-lih-NEE-mee-uh) A condition in which the blood contains high levels of large proteins and is too thick to flow through small blood…
macrophageA type of white blood cell that surrounds and kills microorganisms, removes dead cells, and stimulates the action of other immune system cells.
Maculopathy(Macular Edema) Retinal capillaries become clogged and swollen, leaking fluid into the retina and cause swelling.
mafosfamideA form of cyclophosphamide that can be administered as an intrathecal infusion. Mafosfamide is being studied as an anticancer drug.
magnesium(mag-NEE-zee-um) In medicine, a mineral used by the body to help maintain muscles, nerves, and bones.
magnesium sulfate(mag-NEE-zee-um SUL-fayt) A drug used to treat pre-eclampsia and eclampsia (serious complications of pregnancy).
magnetic resonance imaging(mag-NEH-tik REH-zuh-nunts IH-muh-jing) A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures…
magnetic resonance perfusion imaging(mag-NEH-tik REH-zoh-nants per-FYOO-zhun IH-muh-jing) A special type of magnetic resonance imaging (MRI) that uses an injected dye in order to see blood…
magnetic resonance spectroscopic imaging(mag-NEH-tik REH-zoh-nants SPEK-troh-SKAH-pik IH-muh-jing) A noninvasive imaging method that provides information about cellular activity (metabolic…
magnetic-targeted carrierA tiny bead made from particles of iron and carbon that can be attached to an anticancer drug.
Magnevist(MAG-nuh-vist) A substance used in magnetic resonance imaging (MRI) to help make clear pictures of the brain, spine, heart, soft tissue of joints, and…
maidenhair tree(MAY-din-HAYR...) A tree native to China. Substances taken from the leaves and seeds have been used in some cultures to treat certain medical problems.
mainstream medicine(MAYN-streem MEH-dih-sin) A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat…
maintenance therapy(...THAYR-uh-pee) Treatment that is given to help a primary (original) treatment keep working.
malabsorption syndromeA group of symptoms such as gas, bloating, abdominal pain, and diarrhea resulting from the body's inability to properly absorb nutrients.
malignant ectomesenchymoma(muh-LIG-nunt EK-toh-meh-ZEN-keh-MOH-muh) A rare, fast-growing tumor of the nervous system or soft tissue that occurs in children and young adults.
malignant fibrous cytoma(muh-LIG-nunt FY-brus sy-TOH-muh) A soft tissue sarcoma that usually occurs in the limbs, most commonly the legs, and may also occur in the abdomen.
malignant fibrous histiocytoma(muh-LIG-nunt FY-brus HIS-tee-oh-sy-TOH-muh) A soft tissue sarcoma that usually occurs in the limbs, most commonly the legs, and may also occur in the…
malignant meningioma(muh-LIG-nunt meh-NIN-jee-OH-muh) A rare, fast-growing tumor that forms in one of the inner layers of the meninges (thin layers of tissue that cover and…
malignant mesothelioma(muh-LIG-nunt meh-zuh-thee-lee-OH-muh) A rare type of cancer in which malignant cells are found in the lining of the chest or abdomen.
malignant mixed Müllerian tumor(muh-LIG-nunt ... myoo-LIR-ee-un TOO-mer) A rare type of tumor that is a mixture of carcinoma and sarcoma cells. MMMT usually occurs in the uterus.
malignant peripheral nerve sheath tumor(muh-LIG-nunt peh-RIH-feh-rul ... TOO-mer) A type of soft tissue sarcoma that develops in cells that form a protective sheath (covering) around peripheral…
malignant pleural effusion(muh-LIG-nunt PLOOR-ul eh-FYOO-zhun) A condition in which cancer causes an abnormal amount of fluid to collect between the thin layers of tissue (pleura)…
malnutritionA disorder caused by a lack of proper nutrition or an inability to absorb nutrients from food.
malondialdehydeA byproduct of lipid (fat) metabolism in the body. It is also found in many foods and can be present in high amounts in rancid food.
MALT lymphomaA type of cancer that arises in cells in mucosal tissue that are involved in antibody production. Also called mucosa-associated lymphoid tissue lymphoma.
Mammary dysplasia(MA-muh-ree dis-PLAY-zhuh) A common condition marked by benign (noncancerous) changes in breast tissue.
mammary glandGlandular organ located on the chest. The mammary gland is made up of connective tissue, fat, and tissue that contains the glands that can make milk.
mammography(ma-MAH-gruh-fee) The use of x-rays to create a picture of the breast.
MammotomeA device that uses a computer-guided probe to perform breast biopsies. A Mammotome biopsy can be done on an outpatient basis with a local anesthetic…
mannitol(MA-nih-TOL) A drug used to decrease swelling of the brain and to treat kidney failure.
mantle cell lymphoma(MAN-tul sel lim-FOH-muh) An aggressive (fast-growing) type of B-cell non-Hodgkin lymphoma that usually occurs in middle-aged or older adults.
mantle field(MAN-tul) The area of the neck, chest, and lymph nodes in the armpit that are exposed to radiation.
MAO inhibitor(... in-HIH-bih-ter) A type of drug used to treat depression. It stops the breakdown of certain chemicals in the brain that help improve a person's mood.
Marcaine(MAR-kane) A drug used to relieve pain by blocking signals at nerve endings. It is being studied in the relief of pain following surgery for cancer.
marginal zone B-cell lymphoma(MAR-jih-nul zone B-sel lim-FOH-muh) An indolent (slow-growing) type of B-cell non-Hodgkin lymphoma that begins forming in certain areas (the marginal…
marginal zone lymphoma(MAR-jih-nul zone lim-FOH-muh) An indolent (slow-growing) type of B-cell non-Hodgkin lymphoma that begins forming in certain areas (the marginal zones) of…
Margins(mar' jinz) the distance between the edge of the tissue sample removed and abnormal cells.
maribavir(mar-I-buh-veer) A substance that blocks the ability of viruses to make new viruses and infect cells.
marijuanaA type of plant. Extracts of marijuana are being studied for their ability to control severe nausea and vomiting caused by chemotherapy and/or opioid…
marimastatAn anticancer drug that belongs to the family of drugs called angiogenesis inhibitors. Marimastat is a matrix metalloproteinase inhibitor.
markerA diagnostic indication that disease may develop.
Marketing StatusMarketing status indicates how a drug product is sold in the United States. Drug products in Drugs@FDA are identified as: Prescription Over-the-counter…
MART-1 antigen(..AN-tih-jen) A substance found on the surface of melanoma cells. It is being used to develop cancer vaccines that may help the immune system kill cancer…
masoprocol(mah-SOH-proh-kole) A drug put on the skin to treat growths caused by sun exposure.
massage therapy(muh-SAZH THAYR-uh-pee) A treatment in which the soft tissues of the body are kneaded, rubbed, tapped, and stroked.
mast cell tumorA growth or lump of mast cells (a type of white blood cell). Mast cell tumors can involve the skin, subcutaneous tissue, and muscle tissue.
Mastectomy(ma-STEK-toh-mee) Surgery to remove the breast (or as much of the breast tissue as possible).
mastocytoma(MAS-toh-sy-TOH-muh) A growth or lump of mast cells (a type of white blood cell).
maternal(muh-TUR-nul) Having to do with or coming from the mother.
matrix metalloproteinaseA member of a group of enzymes that can break down proteins, such as collagen, that are normally found in the spaces between cells in tissues (i.e.
mature T-cell lymphomaOne of a group of aggressive (fast-growing) non-Hodgkin lymphomas that begin in mature T lymphocytes (T cells that have matured in the thymus gland and…
mature teratoma(muh-CHOOR TAYR-uh-TOH-muh) A type of benign (noncancerous) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that…
matuzumabA monoclonal antibody that is being studied in the treatment of some types of cancer.
Maxamine(MAX-uh-meen) A substance being studied in the treatment of some types of cancer and other conditions.
MC1RA protein found in skin and eye cells that make melanin (a pigment that gives color to the skin and helps protect it from damage by ultraviolet light).
MDL 101,731A drug that belongs to a family of drugs called ribonucleotide reductase inhibitors.
MDX-010A monoclonal antibody being studied in the treatment of certain types of cancer.
MDX-060A monoclonal antibody that is being studied in the treatment of some lymphomas.
meal planA guide to help people get the proper amount of calories, carbohydrates, proteins, and fats in their diet. See also food exchanges.
MeanA statistics term. The average value in a set of measurements. The mean is the sum of a set of numbers divided by how many numbers are in the set.
mean survival timeThe average time that patients in a clinical study remained alive. The time is measured beginning either at diagnosis or the start of treatment.
measles virus(MEE-zulz VY-rus) The virus that causes measles (a highly contagious disease marked by fever, cough, and raised red spots on the skin).
measurable diseaseA tumor that can be accurately measured in size. This information can be used to judge response to treatment.
mechlorethamine(meh-klor-EH-thuh-meen) A drug used to treat some types of cancer and some precancerous skin conditions.
mechlorethamine hydrochloride(meh-klor-EH-thuh-meen HY-droh-KLOR-ide) A drug used to treat some types of cancer and some precancerous skin conditions.
MEDI-507A monoclonal antibody that is being studied in the treatment of certain lymphoproliferative disorders and psoriasis. Also called siplizumab.
medial supraclavicular lymph node(MEE-dee-ul SOO-pruh-kla-VIH-kyuh-ler...) A lymph node located above the collar bone and between the center of the body and a line drawn through the…
medianA statistics term. The middle value in a set of measurements.
median survival timeThe time from either diagnosis or treatment at which half of the patients with a given disease are found to be, or expected to be, still alive.
median umbilical ligamentA fibrous cord that connects the urinary bladder to the umbilicus (navel). The median umbilical ligament is formed as the allantoic stalk during fetal…
mediastinal pleuraThe thin membrane that lines the chest cavity in the area between the lungs.
mediastinoscope(MEE-dee-uh-STIN-oh-skope) A thin, tube-like instrument used to examine the tissues and lymph nodes in the area between the lungs.
mediastinoscopy(MEE-dee-as-tih-NOS-koh-pee) A procedure in which a mediastinoscope is used to examine the organs in the area between the lungs and nearby lymph nodes.
mediastinum(mee-dee-a-STYE-num) The area between the lungs. The organs in this area include the heart and its large blood vessels, the trachea, the esophagus, the…
Medicaid Spend-downA process whereby an individual who meets the Medicaid medical eligibility criteria, but has income that exceeds the financial eligibility ceiling, may…
medical castrationRefers to the use of drugs to suppress the function of the ovaries or testicles.
medical device(MEH-dih-kul dee-VICE) An instrument, tool, machine, test kit, or implant that is used to prevent, diagnose, or treat disease or other conditions.