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NCI Dictionary of Cancer Terms

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NCI Dictionary of Cancer Terms


480 results found for:       M



M protein    listen   (... 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. Also called monoclonal protein.

M-EDTA      
A substance being studied in the prevention of bacterial infections that occur in catheters (thin tubes that carry fluids into or out of the body). It is a combination of minocycline, an antibiotic that blocks the growth of bacteria, and EDTA, a substance that keeps blood clots from forming. M-EDTA removes metals that bacteria use to form biofilms (thin layers stuck to surfaces). Also called minocycline-EDTA.

M200      
A monoclonal antibody that is being studied in the treatment of some types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. M200 binds to a protein that is found on cells that line some tumor blood vessels. It is a type of angiogenesis inhibitor. Also called volociximab.

ma huang    listen   (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. It has also been promoted as a decongestant, a weight loss aid, and as a supplement to increase energy. Ma huang may cause high blood pressure, increased heart rate, or death if used with certain drugs, and may reduce the effects of certain drugs used to treat cancer and other diseases. The U.S. Food and Drug Administration has banned the sale of dietary supplements that contain ma huang. The scientific name is Ephedra sinica. Also called ephedra.

macrocalcification    listen   (MA-kroh-KAL-sih-fih-KAY-shun)
A small deposit of calcium in the breast that cannot be felt but can be seen on a mammogram. It is usually caused by aging, an old injury, or inflamed tissue and is usually not related to cancer.

macroglobulinemia    listen   (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 vessels. One type is Waldenström macroglobulinemia, which is a type of cancer.

macrophage    listen   (MA-kroh-fayj)
A type of white blood cell that surrounds and kills microorganisms, removes dead cells, and stimulates the action of other immune system cells.

macular degeneration    listen   (MA-kyoo-ler dee-JEH-neh-RAY-shun)
A condition in which there is a slow breakdown of cells in the center of the retina (the light-sensitive layers of nerve tissue at the back of the eye). This blocks vision in the center of the eye and can cause problems with activities such as reading and driving. Macular degeneration is most often seen in people who are over the age of 50. Also called age-related macular degeneration, AMD, and ARMD.

mafosfamide    listen   (muh-FOS-fuh-mide)
A form of cyclophosphamide that can be administered as an intrathecal infusion. Mafosfamide is being studied as an anticancer drug. It belongs to the family of drugs called alkylating agents.

MAGE-3 antigen    listen   (... AN-tih-jen)
A protein found in many types of tumors but not in most normal tissues. Vaccines using pieces of the MAGE-3 protein are being studied for their ability to boost the immune response to cancer cells in patients with cancer.

magnesium    listen   (mag-NEE-zee-um)
In medicine, a mineral used by the body to help maintain muscles, nerves, and bones. It is also used in energy metabolism and protein synthesis.

magnesium sulfate    listen   (mag-NEE-zee-um SUL-fayt)
A drug used to treat pre-eclampsia and eclampsia (serious complications of pregnancy). Magnesium sulfate is also being studied for its ability to prevent the toxic side effects of certain drugs used to treat colorectal cancer. It is a type of anticonvulsant agent.

magnetic resonance angiography    listen   (mag-NEH-tik REH-zuh-nunts an-jee-AH-gruh-fee)
A procedure that uses radio waves and a powerful magnet linked to a computer to create detailed pictures of the blood vessels and blood flow inside the body. A dye may be injected into a vein to make the blood vessels and blood flow easier to see. Magnetic resonance angiography may be used to check for aneurysms (a bulge in the blood vessel wall), blockages in the arteries, blood clots, and other blood vessel problems. Also called MRA.

magnetic resonance imaging    listen   (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 of areas inside the body. These pictures can show the difference between normal and diseased tissue. Magnetic resonance imaging makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. Magnetic resonance imaging is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called MRI, NMRI, and nuclear magnetic resonance imaging.

magnetic resonance perfusion imaging    listen   (mag-NEH-tik REH-zuh-nunts per-FYOO-zhun IH-muh-jing)
A special type of magnetic resonance imaging (MRI) that uses an injected dye in order to see blood flow through tissues. Also called perfusion magnetic resonance imaging.

magnetic resonance spectroscopic imaging    listen   (mag-NEH-tik REH-zuh-nunts SPEK-troh-SKAH-pik IH-muh-jing)
A noninvasive imaging method that provides information about cellular activity (metabolic information). It is used along with magnetic resonance imaging (MRI) which provides information about the shape and size of the tumor (spatial information). Also called 1H-nuclear magnetic resonance spectroscopic imaging, MRSI, and proton magnetic resonance spectroscopic imaging.

magnetic-targeted carrier    listen   (mag-NEH-tik-TAR-geh-ted KAYR-ee-er)
A tiny bead made from particles of iron and carbon that can be attached to an anticancer drug. A magnet applied from outside the body then can direct the drug to the tumor site. This can keep a larger dose of the drug at the tumor site for a longer period of time, and help protect healthy tissue from the side effects of chemotherapy.

Magnevist    listen   (MAG-neh-vist)
A substance used in magnetic resonance imaging (MRI) to help make clear pictures of the brain, spine, heart, soft tissue of joints, and inside bones. Magnevist is being studied in the diagnosis of cancer. It is a type of contrast agent. Also called gadopentetate dimeglumine and Gd-DTPA.

maidenhair tree    listen   (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. Maidenhair tree has been studied in the prevention and treatment of Alzheimer disease, dementia, certain blood vessel diseases, and memory loss. It may cause bleeding or high blood pressure when used with certain drugs. Also called ginkgo and ginkgo biloba.

mainstream medicine    listen   (MAYN-streem MEH-dih-sin)
A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery. Also called allopathic medicine, biomedicine, conventional medicine, orthodox medicine, and Western medicine.

mainstream smoke    listen   (MAYN-streem ...)
Tobacco smoke that is exhaled by smokers. Mainstream smoke can be a form of secondhand smoke. It contains nicotine and many harmful, cancer-causing chemicals. Inhaling mainstream smoke increases the risk of lung cancer and may increase the risk of other types of cancer. Inhaling it also increases the risk of other health problems, such as heart disease and lung disease.

maintenance therapy    listen   (MAYN-teh-nunts THAYR-uh-pee)
Treatment that is given to help keep cancer from coming back after it has disappeared following the initial therapy. It may include treatment with drugs, vaccines, or antibodies that kill cancer cells, and it may be given for a long time.

malabsorption syndrome    listen   (MA-lub-SORP-shun SIN-drome)
A group of symptoms such as gas, bloating, abdominal pain, and diarrhea resulting from the body's inability to properly absorb nutrients.

male breast cancer    listen   (mayl brest KAN-ser)
Cancer that forms in tissues of the breast in men. Most male breast cancer begins in cells lining the ducts. It is very rare and usually affects older men.

malignancy    listen   (muh-LIG-nun-see)
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Malignant cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of malignancy. Carcinoma is a malignancy that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a malignancy that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a malignancy that starts in blood-forming tissue, such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are malignancies that begin in the cells of the immune system. Central nervous system cancers are malignancies that begin in the tissues of the brain and spinal cord. Also called cancer.

malignant    listen   (muh-LIG-nunt)
Cancerous. Malignant cells can invade and destroy nearby tissue and spread to other parts of the body.

malignant ascites    listen   (muh-LIG-nunt uh-SY-teez)
A condition in which fluid containing cancer cells collects in the abdomen.

malignant ectomesenchymoma    listen   (muh-LIG-nunt EK-toh-MEH-zen-ky-MOH-muh)
A rare, fast-growing tumor of the nervous system or soft tissue that occurs in children and young adults. Malignant ectomesenchymomas may form in the head and neck, abdomen, perineum, scrotum, or limbs. Also called ectomesenchymoma.

malignant fibrous cytoma    listen   (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. Also called malignant fibrous histiocytoma.

malignant fibrous histiocytoma    listen   (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 abdomen. Also called malignant fibrous cytoma.

malignant meningioma    listen   (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 protect the brain and spinal cord). Malignant meningioma often spreads to other areas of the body.

malignant mesothelioma    listen   (muh-LIG-nunt MEH-zoh-THEE-lee-OH-muh)
A rare type of cancer in which malignant cells are found in the lining of the chest or abdomen. Exposure to airborne asbestos particles increases one's risk of developing malignant mesothelioma.

malignant mixed Müllerian tumor    listen   (muh-LIG-nunt mikst myoo-LAYR-ee-un TOO-mer)
A rare type of tumor that is a mixture of carcinoma and sarcoma cells. MMMT usually occurs in the uterus. Also called MMMT.

malignant peripheral nerve sheath tumor    listen   (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 nerves, which are nerves that are outside of the central nervous system (brain and spinal cord). Also called MPNST.

malignant pleural effusion    listen   (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) lining the outside of the lung and the wall of the chest cavity. Lung cancer, breast cancer, lymphoma, and leukemia cause most malignant pleural effusions.

malnourished    listen   (mal-NER-isht)
Describes a condition caused by not getting enough calories or the right amount of key nutrients needed for health. Key nutrients include vitamins and minerals.

malnutrition    listen   (mal-noo-TRIH-shun)
A condition caused by not getting enough calories or the right amount of key nutrients, such as vitamins and minerals, that are needed for health. Malnutrition may occur when there is a lack of nutrients in the diet or when the body cannot absorb nutrients from food. Cancer and cancer treatment may cause malnutrition.

malondialdehyde    listen   (MA-lon-dy-AL-deh-hide)
A 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 lymphoma    listen   (... lim-FOH-muh)
A type of cancer that arises in cells in mucosal tissue that are involved in antibody production. Also called mucosa-associated lymphoid tissue lymphoma.

mammalian target of rapamycin    listen   (muh-MA-lee-un TAR-get … RA-puh-MY-sin)
A protein that helps control several cell functions, including cell division and survival, and binds to rapamycin and other drugs. Mammalian target of rapamycin may be more active in some types of cancer cells than it is in normal cells. Blocking mammalian target of rapamycin may cause the cancer cells to die. It is a type of serine/threonine protein kinase. Also called mTOR.

MammaPrint    listen   (MA-muh-print)
A test that is used to help predict whether breast cancer has spread to other parts of the body or come back. The test looks at the activity of 70 different genes in breast cancer tissue of women who have early-stage breast cancer that has not spread to the lymph nodes. If there is a high risk that the cancer will spread or come back, it may be used to help plan treatment with anticancer drugs. Also called 70-gene signature.

mammary    listen   (MA-muh-ree)
Having to do with the breast.

mammary dysplasia    listen   (MA-muh-ree dis-PLAY-zhuh)
A common condition marked by benign (not cancer) changes in breast tissue. These changes may include irregular lumps or cysts, breast discomfort, sensitive nipples, and itching. These symptoms may change throughout the menstrual cycle and usually stop after menopause. Also called benign breast disease, fibrocystic breast changes, and fibrocystic breast disease.

mammary gland    listen   (MA-muh-ree ...)
Glandular 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. Also called breast.

mammogram    listen   (MA-muh-gram)
An x-ray of the breast.

mammography    listen   (ma-MAH-gruh-fee)
The use of film or a computer to create a picture of the breast.

MammoSite    listen   (MA-moh-site)
A system used to deliver internal radiation therapy to breast cancer patients after surgery to remove their cancer. MammoSite targets only the part of the breast where the cancer was found. After a patient has had a lumpectomy to remove the cancer, a small balloon on the end of a catheter (thin tube) is inserted into the empty space left by the surgery. The balloon is then filled with liquid and left in place. Using the catheter, radioactive seeds are put into the balloon twice a day for five days and removed each time. Once treatment has ended, the catheter and balloon are removed. MammoSite is a type of intracavitary brachytherapy and partial breast irradiation therapy (PBRT). Also called balloon catheter radiation.

Mammotome    listen   (MA-moh-tome)
A 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, removes only a small amount of healthy tissue, and doesn’t require sutures (stitches) because the incision is very small.

manipulative and body-based practice    listen   (muh-NIP-yoo-luh-tiv ... BAH-dee-bayst PRAK-tis)
A type of therapy in which the therapist moves or manipulates one or more parts of the patient’s body. It may be used to treat pain, stress, anxiety, and depression, and for general well-being. Examples include chiropractic treatments, physical therapy, and massage therapy. Also called manual healing and physical touch methods.

mannitol    listen   (MA-nih-TOL)
A drug used to decrease swelling of the brain and to treat kidney failure. Mannitol can also be used to open the blood-brain barrier, which allows anticancer medicines to enter the brain and treat brain tumors.

mantle cell lymphoma    listen   (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. It is marked by small- to medium-size cancer cells that may be in the lymph nodes, spleen, bone marrow, blood, and gastrointestinal system.

mantle field    listen   (MAN-tul ...)
The area of the neck, chest, and lymph nodes in the armpit that are exposed to radiation.

manual healing    listen   (MAN-yoo-ul HEE-ling)
A type of therapy in which the therapist moves or manipulates one or more parts of the patient’s body. It may be used to treat pain, stress, anxiety, and depression, and for general well-being. Examples include chiropractic treatments, physical therapy, and massage therapy. Also called manipulative and body-based practice and physical touch methods.

MAO inhibitor    listen   (... 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. A MAO inhibitor is a type of antidepressant. Also called monoamine oxidase inhibitor.

mapatumumab    listen   (ma-puh-TOO-moo-mab)
A substance being studied in the treatment of some types of cancer. It binds to a protein called TRAIL R1 on the surface of some tumor cells. This may kill the tumor cells. Mapatumumab is a type of monoclonal antibody. Also called anti-TRAIL R1-mAb and HGS-ETR1.

Marcaine    listen   (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. It is a type of local anesthetic. Also called bupivacaine, bupivacaine hydrochloride, and Sensorcaine.

margin    listen   (MAR-jin)
The edge or border of the tissue removed in cancer surgery. The margin is described as negative or clean when the pathologist finds no cancer cells at the edge of the tissue, suggesting that all of the cancer has been removed. The margin is described as positive or involved when the pathologist finds cancer cells at the edge of the tissue, suggesting that all of the cancer has not been removed.

marginal zone B-cell lymphoma    listen   (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 zones) of lymph tissue. There are three types based on whether it forms in the spleen, lymph nodes, or other lymphoid tissue that contains a lot of B cells (a type of white blood cell). Also called marginal zone lymphoma and MZL.

marginal zone lymphoma    listen   (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 lymph tissue. There are three types based on whether it forms in the spleen, lymph nodes, or other lymphoid tissue that contains a lot of B cells (a type of white blood cell). Also called marginal zone B-cell lymphoma and MZL.

maribavir    listen   (mar-I-buh-veer)
A substance that blocks the ability of viruses to make new viruses and infect cells. It is being studied in the prevention of cytomegalovirus infection in cancer patients who have had a donor stem cell transplant. It is a type of antiviral agent.

marijuana    listen   (MAYR-ih-WAH-nuh)
The dried leaves and flowering tops of the Cannabis sativa or Cannabis indica plant. Marijuana contains active chemicals called cannabinoids that cause drug-like effects all through the body, including the central nervous system and the immune system. Marijuana may help treat the symptoms of cancer or the side effects of cancer treatment, such as nausea and vomiting, pain, and cachexia (loss of body weight and muscle mass). Also called Cannabis.

marimastat    listen   (muh-RIH-muh-stat)
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors. Marimastat is a matrix metalloproteinase inhibitor.

marker    listen   (MAR-ker)
A diagnostic indication that disease may develop.

Marqibo    listen   (MAR-kee-boh)
A form of the anticancer drug vincristine sulfate that is contained inside very tiny, fat-like particles. It may have fewer side effects and work better than vincristine. Marqibo is used to treat adults with acute lymphoblastic leukemia that is Philadelphia chromosome negative and has come back or has not gotten better with other treatment. It is also being studied in the treatment of other types of cancer. It is a type of vinca alkaloid and a type of antimitotic agent. Also called liposomal vincristine sulfate and vincristine sulfate liposome.

MART-1 antigen    listen   (... AN-tih-jen)
A protein found on normal melanocytes (cells that make the pigment melanin) in the skin and in the retina. It is also found on most melanomas (cancers that begin in melanocytes). Vaccines using pieces of the MART-1 antigen are being studied for their ability to boost the immune response to cancer cells in patients with melanoma. Also called Melan-A protein and Melanoma Antigen Recognized by T cells 1.

masoprocol    listen   (muh-SOH-proh-kol)
A drug put on the skin to treat growths caused by sun exposure. A form of masoprocol that is taken by mouth is being studied in the treatment of prostate cancer. Masoprocol is an antioxidant, and it may block certain enzymes needed for tumor growth. Also called Actinex, NDGA, and nordihydroguaiaretic acid.

mass    listen   (mas)
In medicine, a lump in the body. It may be caused by the abnormal growth of cells, a cyst, hormonal changes, or an immune reaction. A mass may be benign (not cancer) or malignant (cancer).

massage therapy    listen   (muh-SAZH THAYR-uh-pee)
A treatment in which the soft tissues of the body are kneaded, rubbed, tapped, and stroked. Massage therapy may help people relax, relieve stress and pain, lower blood pressure, and improve circulation. It is being studied in the treatment of cancer symptoms such as lack of energy, pain, swelling, and depression.

mast cell    listen   (mast sel)
A type of white blood cell.

mast cell tumor    listen   (mast sel TOO-mer)
A growth or lump of mast cells (a type of white blood cell). Mast cell tumors can involve the skin, subcutaneous tissue, and muscle tissue. Also called mastocytoma.

mastectomy    listen   (ma-STEK-toh-mee)
Surgery to remove part or all of the breast. There are different types of mastectomy that differ in the amount of tissue and lymph nodes removed.

mastitis    listen   (ma-STY-tis)
A condition in which breast tissue is inflamed. It is usually caused by an infection and is most often seen in nursing mothers.

mastocytoma    listen   (MAS-toh-sy-TOH-muh)
A growth or lump of mast cells (a type of white blood cell). Mast cell tumors can involve the skin, subcutaneous tissue, and muscle tissue. Also called mast cell tumor.

maternal    listen   (muh-TER-nul)
Having to do with the mother, coming from the mother, or related through the mother.

matrix metalloproteinase    listen   (MAY-trix meh-TA-loh-PROH-tee-nays)
A 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., extracellular matrix proteins). Because these enzymes need zinc or calcium atoms to work properly, they are called metalloproteinases. Matrix metalloproteinases are involved in wound healing, angiogenesis, and tumor cell metastasis.

Matulane    listen   (MA-choo-layn)
A drug that is used to treat advanced Hodgkin lymphoma and is being studied in the treatment of other types of cancer. Matulane blocks cells from making proteins and damages DNA. It may kill cancer cells. It is a type of antineoplastic agent and a type of alkylating agent. Also called procarbazine hydrochloride.

mature T-cell lymphoma    listen   (muh-CHOOR T-sel lim-FOH-muh)
One 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 gone to other lymphatic sites in the body, including lymph nodes, bone marrow, and spleen.) Also called peripheral T-cell lymphoma.

mature teratoma    listen   (muh-CHOOR TAYR-uh-TOH-muh)
A type of benign (not cancer) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that often contains several different types of tissue such as hair, muscle, and bone. Also called dermoid cyst.

Maxamine    listen   (MAK-suh-meen)
A substance being studied in the treatment of some types of cancer and other conditions. When used together with interleukin-2, Maxamine may help some immune cells find and kill tumor cells. It is a type of biological response modifier. Also called histamine dihydrochloride.

maxillary sinus    listen   (MAK-sih-LAYR-ee SY-nus)
A type of paranasal sinus (a hollow space in the bones around the nose). There are two large maxillary sinuses, one in each of the maxillary bones, which are in the cheek area next to the nose. The maxillary sinuses are lined with cells that make mucus to keep the nose from drying out.

maximum inspiratory pressure test    listen   (MAK-sih-mum in-SPY-ruh-TOR-ee PREH-sher…)
A test that measures the strength of the muscles used in breathing. A person inhales and exhales through a device called a manometer, and the pressures are recorded by a computer. Also called MIP test.

maximum tolerated dose    listen   (MAK-sih-mum TAH-leh-RAY-ted …)
The highest dose of a drug or treatment that does not cause unacceptable side effects. The maximum tolerated dose is determined in clinical trials by testing increasing doses on different groups of people until the highest dose with acceptable side effects is found. Also called MTD.

Mayo Clinic regimen    listen   (MAY-oh KLIH-nik REH-jih-men)
A chemotherapy combination used to treat colorectal cancer. It is also used with radiation therapy to treat esophageal cancer and stomach cancer. It includes the drugs fluorouracil and leucovorin calcium.

maytansinoid DM4-conjugated humanized monoclonal antibody huC242    listen   (may-TAN-sih-noyd DM4-KON-juh-GAY-ted HYOO-muh-nized MAH-noh-KLOH-nul AN-tee-BAH-dee...)
A substance being studied in the treatment of some types of cancer. It is made by linking the monoclonal antibody huC242 to a toxic substance called maytansinoid DM4. The monoclonal antibody binds to the surfaces of cancer cells and the maytansinoid DM4 enters the cells and blocks their growth. It is a type of immunotoxin. Also called huC242-DM4.

MBL      
A condition in which a higher-than-normal number of identical B cells are found in the blood. People with MBL may develop other B-cell diseases, such as chronic lymphocytic leukemia (CLL). Also called monoclonal B-cell lymphocytosis.

MC1R      
A 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). People with certain changes in the gene for MC1R have a higher risk of developing melanoma (skin cancer that begins in melanocytes). Also called melanocortin 1 receptor and melanotropin receptor.

MC5-A scrambler therapy    listen   (… SKRAM-bler THAYR-uh-pee)
A type of treatment for nerve pain that uses electrodes placed on the skin. Electricity is carried from the electrodes through the skin and blocks the pain. The pain may be caused by physical injury, infection, toxic substances, and certain diseases or drugs, including anticancer drugs.

MDL 101,731      
A drug that belongs to a family of drugs called ribonucleotide reductase inhibitors.

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

MDS      
A type of cancer in which the bone marrow does not make enough healthy blood cells (white blood cells, red blood cells, and platelets) and there are abnormal cells in the blood and/or bone marrow. When there are fewer healthy blood cells, infection, anemia, or bleeding may occur. Sometimes, MDS becomes acute myeloid leukemia (AML). Also called myelodysplastic syndrome.

MDX-010      
A drug used to treat melanoma that has spread to other parts of the body or that cannot be removed by surgery. It is also being studied in the treatment of other types of cancer. MDX-010 binds to a substance called CTLA-4, which is found on the surface of T cells (a type of white blood cell). MDX-010 may block CTLA-4 and help the immune system kill cancer cells. It is a type of monoclonal antibody. Also called ipilimumab and Yervoy.

MDX-060      
A monoclonal antibody that is being studied in the treatment of some lymphomas. Monoclonal antibodies are produced in the laboratory and can locate and bind to cancer cells.

mean    listen   (meen)
A 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    listen   (meen ser-VY-vul)
The average length of time from either the date of diagnosis or the start of treatment for a disease, such as cancer, that patients diagnosed with the disease are still alive. In a clinical trial, measuring mean survival is one way to see how well a new treatment works.

measles virus    listen   (MEE-zulz VY-rus)
The virus that causes measles (a highly contagious disease marked by fever, cough, and raised red spots on the skin). The measles virus usually affects children, and is spread by coughing or contact with fluid from the nose or mouth of someone who has been infected.

measurable disease    listen   (MEH-zur-uh-bul dih-ZEEZ)
A tumor that can be accurately measured in size. This information can be used to judge response to treatment.

mechlorethamine hydrochloride    listen   (meh-klor-EH-thuh-meen HY-droh-KLOR-ide)
A drug used to treat non-Hodgkin lymphoma, advanced Hodgkin lymphoma, chronic leukemia, mycosis fungoides, and a type of lung cancer called bronchogenic carcinoma. It is also being studied in the treatment of other types of cancer. Mechlorethamine hydrochloride damages the cell's DNA and may kill cancer cells. It is a type of alkylating agent. Also called Mustargen and mustine.

MEDI-507      
A substance being studied in the treatment of certain types of T-cell lymphoma. It is also being studied in the prevention of organ or tissue rejection after a kidney and/or bone marrow transplant. MEDI-507 binds to a protein called CD2, which is found on some types of immune cells and cancer cells. This may help suppress the body’s immune response and it may help kill cancer cells. MEDI-507 is a type of monoclonal antibody. Also called siplizumab.

MEDI-522      
A substance being studied in the treatment of some types of cancer and other conditions. MEDI-522 binds to a protein on the surface of blood vessels and may prevent the growth of new blood vessels that tumors need to grow. It may also prevent the spread of cancer. It is a type of antiangiogenesis agent, a type of metastasis inhibitor, and a type of monoclonal antibody. Also called Abegrin, etaracizumab, and humanized monoclonal antibody MEDI-522.

medial supraclavicular lymph node    listen   (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 nipple to the shoulder.

median    listen   (MEE-dee-un)
A statistics term. The middle value in a set of measurements.

median overall survival    listen   (MEE-dee-un oh-ver-AWL ser-VY-vul)
The length of time from either the date of diagnosis or the start of treatment for a disease, such as cancer, that half of the patients in a group of patients diagnosed with the disease are still alive. In a clinical trial, measuring the median overall survival is one way to see how well a new treatment works. Also called median survival.

median survival    listen   (MEE-dee-un ser-VY-vul)
The length of time from either the date of diagnosis or the start of treatment for a disease, such as cancer, that half of the patients in a group of patients diagnosed with the disease are still alive. In a clinical trial, measuring the median survival is one way to see how well a new treatment works. Also called median overall survival.

median umbilical ligament    listen   (MEE-dee-un um-BIH-lih-kul LIH-guh-ment)
A fibrous cord that connects the urinary bladder to the umbilicus (navel). The median umbilical ligament is formed as the allantoic stalk during fetal development and lasts through life. Also called urachus.

mediastinal pleura    listen   (MEE-dee-uh-STY-nul PLOOR-uh)
The thin membrane that lines the chest cavity in the area between the lungs.

mediastinoscope    listen   (MEE-dee-uh-STY-noh-skope)
A thin, tube-like instrument used to examine the tissues and lymph nodes in the area between the lungs. These tissues include the heart and its large blood vessels, trachea, esophagus, and bronchi. The mediastinoscope has a light and a lens for viewing and may also have a tool to remove tissue. It is inserted into the chest through a cut above the breastbone.

mediastinoscopy    listen   (MEE-dee-uh-sty-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. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. The mediastinoscope is inserted into the chest through an incision above the breastbone. This procedure is usually done to get a tissue sample from the lymph nodes on the right side of the chest.

mediastinum    listen   (MEE-dee-uh-STY-num)
The area between the lungs. The organs in this area include the heart and its large blood vessels, the trachea, the esophagus, the thymus, and lymph nodes but not the lungs.

Medicaid    listen   (MEH-dih-kayd)
A health insurance program for people who cannot afford regular medical care. The program is run by U.S. federal, state, and local governments. People who receive Medicaid may have to pay a small amount for the services they get.

medical castration    listen   (MEH-dih-kul kas-TRAY-shun)
Refers to the use of drugs to suppress the function of the ovaries or testicles.

medical device    listen   (MEH-dih-kul dee-VISE)
An instrument, tool, machine, test kit, or implant that is used to prevent, diagnose, or treat disease or other conditions. Medical devices range from tongue depressors to heart pacemakers and medical imaging equipment.

medical history    listen   (MEH-dih-kul HIH-stuh-ree)
A record of information about a person’s health. A personal medical history may include information about allergies, illnesses, surgeries, immunizations, and results of physical exams and tests. It may also include information about medicines taken and health habits, such as diet and exercise. A family medical history includes health information about a person’s close family members (parents, grandparents, children, brothers, and sisters). This includes their current and past illnesses. A family medical history may show a pattern of certain diseases in a family.

medical nutrition therapy    listen   (MEH-dih-kul noo-TRIH-shun THAYR-uh-pee)
Treatment based on nutrition. It includes checking a person’s nutrition status, and giving the right foods or nutrients to treat conditions such as those caused by diabetes, heart disease, and cancer. It may involve simple changes in a person’s diet, or intravenous or tube feeding. Medical nutrition therapy may help patients recover more quickly and spend less time in the hospital. Also called nutrition therapy.

medical oncologist    listen   (MEH-dih-kul on-KAH-loh-jist)
A doctor who specializes in diagnosing and treating cancer using chemotherapy, hormonal therapy, biological therapy, and targeted therapy. A medical oncologist often is the main health care provider for someone who has cancer. A medical oncologist also gives supportive care and may coordinate treatment given by other specialists.

Medicare    listen   (MEH-dih-kayr)
A U.S. federal health insurance program for people aged 65 years or older and people with certain disabilities. Medicare pays for hospital stays, medical services, and some prescription drugs but people who receive Medicare must pay part of their healthcare costs.

medicated urethral system for erection    listen   (MEH-dih-KAY-ted yoo-REE-thrul SIS-tem … eh-REK-shun)
A method used to treat impotence (inability to have an erection). A suppository, in the form of a very small pellet, is inserted through the tip of the penis into the urethra. The suppository contains the drug alprostadil, which increases the flow of blood to the penis and causes an erection. Also called MUSE.

medication    listen   (MEH-dih-KAY-shun)
A legal drug that is used to prevent, treat, or relieve symptoms of a disease or abnormal condition.

medicine    listen   (MEH-dih-sin)
Refers to the practices and procedures used for the prevention, treatment, or relief of symptoms of a diseases or abnormal conditions. This term may also refer to a legal drug used for the same purpose.

meditation    listen   (MEH-dih-TAY-shun)
A mind-body practice in which a person focuses his or her attention on something, such as an object, word, phrase, or breathing, in order to minimize distracting or stressful thoughts or feelings. Meditation may help relax the body and mind and improve overall health and well-being. It may be used to help relieve stress, pain, anxiety, and depression and to help with symptoms related to disease, such as cancer and AIDS. It is a type of complementary and alternative medicine (CAM).

medroxyprogesterone    listen   (meh-DROK-see-proh-JES-teh-rone)
A hormonal anticancer drug that is also used in cancer prevention. It belongs to the family of drugs called progestins.

medroxyprogesterone acetate    listen   (meh-DROK-see-proh-JES-teh-rone A-seh-tayt)
A drug used to prevent endometrial cancer. It is also used to treat menstrual disorders and as a form of birth control. It is a form of the female hormone progesterone and belongs to the family of drugs called progestins.

medullary breast carcinoma    listen   (MED-yoo-LAYR-ee brest KAR-sih-NOH-muh)
A rare type of breast cancer that often can be treated successfully. It is marked by lymphocytes (a type of white blood cell) in and around the tumor that can be seen when viewed under a microscope.

medullary thyroid cancer    listen   (MED-yoo-LAYR-ee THY-royd KAN-ser)
Cancer that develops in C cells of the thyroid. The C cells make a hormone (calcitonin) that helps maintain a healthy level of calcium in the blood.

medulloblastoma    listen   (MED-yoo-loh-blas-TOH-muh)
A malignant brain tumor that begins in the lower part of the brain and that can spread to the spine or to other parts of the body. Medulloblastomas are a type of primitive neuroectodermal tumor (PNET).

mega-voltage linear accelerator    listen   (MEH-guh-VOLE-tij LIH-nee-er ak-SEH-leh-RAY-ter)
A machine that uses electricity to form a stream of fast-moving subatomic particles. This creates high-energy radiation that may be used to treat cancer. Also called linac, linear accelerator, and MeV linear accelerator.

Megace    listen   (meh-GAYS)
A drug used to treat advanced breast and endometrial cancer. It is also used to treat anorexia (loss of appetite) and cachexia (weakness and loss of body weight and muscle mass) in patients with AIDS. It is also being studied in the treatment of anorexia and cachexia in patients with cancer or other conditions. Megace blocks the effects of the hormone estrogen in the body, which may help keep some cancer cells from growing. It may also improve appetite. Megace is a type of progestin. Also called megestrol acetate.

megestrol acetate    listen   (meh-JES-trol A-seh-tayt)
A drug used to treat advanced breast and endometrial cancer. It is also used to treat anorexia (loss of appetite) and cachexia (weakness and loss of body weight and muscle mass) in patients with AIDS. It is also being studied in the treatment of anorexia and cachexia in patients with cancer or other conditions. Megestrol acetate blocks the effects of the hormone estrogen in the body, which may help keep some cancer cells from growing. It may also improve appetite. Megestrol acetate is a type of progestin. Also called Megace.

meiosis    listen   (my-OH-sis)
A special form of cell division in which each daughter cell receives half the amount of DNA as the parent cell. Meiosis occurs during formation of egg and sperm cells in mammals.

MEK inhibitor AZD6244    listen   (... in-HIH-bih-ter...)
A substance being studied in the treatment of several types of cancer. MEK inhibitor AZD6244 blocks proteins needed for cell growth and may kill cancer cells. It is a type of protein kinase inhibitor. Also called AZD6244 and selumetinib.

Mekinist    listen   (MEH-kih-nist)
A drug used alone or with dabrafenib to treat melanoma that cannot be removed by surgery or has spread to other parts of the body. It is used in patients with a mutated (changed) form of a cell protein called BRAF. It is also being studied in the treatment of other types of cancer. Mekinist blocks certain proteins, which may help keep cancer cells from growing and may kill them. It is a type of kinase inhibitor and a type of targeted therapy. Also called trametinib.

Melan-A protein    listen   (MEH-lun … PROH-teen)
A protein found on normal melanocytes (cells that make the pigment melanin) in the skin and in the retina. It is also found on most melanomas (cancers that begin in melanocytes). Vaccines using pieces of the Melan-A protein are being studied for their ability to boost the immune response to cancer cells in patients with melanoma. Also called MART-1 antigen and Melanoma Antigen Recognized by T cells 1.

melanin    listen   (MEH-luh-nin)
A pigment that gives color to skin and eyes and helps protect it from damage by ultraviolet light.

melanocortin 1 receptor    listen   (MEH-luh-noh-KOR-tin 1 reh-SEP-ter)
A 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). People with certain changes in the gene for melanocortin 1 receptor have a higher risk of developing melanoma (skin cancer that begins in melanocytes). Also called MC1R and melanotropin receptor.

melanocyte    listen   (meh-LAN-oh-site)
A cell in the skin and eyes that produces and contains the pigment called melanin.

melanoma    listen   (MEH-luh-NOH-muh)
A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.

Melanoma Antigen Recognized by T cells 1    listen   (MEH-luh-NOH-muh AN-tih-jen REH-kug-NIZED …)
A protein found on normal melanocytes (cells that make the pigment melanin) in the skin and in the retina. It is also found on most melanomas (cancers that begin in melanocytes). Vaccines using pieces of the Melanoma Antigen Recognized by T cells 1 are being studied for their ability to boost the immune response to cancer cells in patients with melanoma. Also called MART-1 antigen and Melan-A protein.

melanoma in situ    listen   (MEH-luh-NOH-muh in SY-too)
Abnormal melanocytes (cells that make melanin, the pigment that gives skin its color) are found in the epidermis (outer layer of the skin). These abnormal melanocytes may become cancer and spread into nearby normal tissue. Also called stage 0 melanoma.

melanoma vaccine    listen   (MEH-luh-NOH-muh vak-SEEN)
A cancer vaccine prepared from human melanoma cancer cells. It can be used alone or with other therapy in treating melanoma.

melanotropin receptor    listen   (MEH-luh-noh-TROH-pin reh-SEP-ter)
A 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). People with certain changes in the gene for melanotropin receptor have a higher risk of developing melanoma (skin cancer that begins in melanocytes). Also called MC1R and melanocortin 1 receptor.

melatonin    listen   (MEH-luh-TOH-nin)
A hormone made by the pineal gland (tiny organ near the center of the brain). Melatonin helps control the body’s sleep cycle, and is an antioxidant. It is also made in the laboratory and sold as a supplement.

melphalan    listen   (MEL-fuh-lan)
A drug that is used to treat multiple myeloma and ovarian epithelial cancer and is being studied in the treatment of other types of cancer. It belongs to the family of drugs called alkylating agents. Also called Alkeran.

memantine hydrochloride    listen   (MEH-mun-teen HY-droh-KLOR-ide)
A drug used to treat dementia caused by Alzheimer disease. It is also being studied in the treatment of side effects from whole-brain radiation therapy for cancer and other conditions. Memantine hydrochloride blocks the uptake of calcium by certain brain cells and decreases their activity. It is a type of N-methyl-D-asparatate (NMDA) receptor antagonist. Also called Namenda.

membrane    listen   (MEM-brayn)
A very thin layer of tissue that covers a surface.

MEN syndrome    listen   (... SIN-drome)
An inherited condition that may result in the development of cancers of the endocrine system. There are several types of MEN syndrome, and patients with each type may develop different types of cancer. The altered genes that cause each type can be detected with a blood test. Also called multiple endocrine neoplasia syndrome.

MEN-10755      
An anticancer drug that belongs to the family of drugs called antitumor antibiotics.

MEN1 syndrome    listen   (... SIN-drome)
A rare, inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid and pituitary glands and the pancreas. These tumors are usually benign (not cancer). They cause the glands to secrete high levels of hormones, which can lead to other medical problems, such as kidney stones, fertility problems, and severe ulcers. In some cases, tumors inside the pancreas can become malignant (cancer). Also called multiple endocrine adenomatosis, multiple endocrine neoplasia type 1 syndrome, and Wermer syndrome.

MEN2      
A rare, genetic disorder that affects the endocrine glands and can cause tumors in the thyroid gland, parathyroid glands, and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. MEN2 is caused by a mutation (change) in a gene called RET, and is divided into three subtypes (MEN2A, MEN2B, and FMTC). People with all subtypes of MEN2 have an increased risk of medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. Also called MEN2 syndrome, multiple endocrine adenomatosis type 2, and multiple endocrine neoplasia type 2 syndrome.

MEN2 syndrome    listen   (... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and can cause tumors in the thyroid gland, parathyroid glands, and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. MEN2 syndrome is caused by a mutation (change) in a gene called RET, and is divided into three subtypes (MEN2A, MEN2B, and FMTC). People with all subtypes of MEN2 syndrome have an increased risk of medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. Also called MEN2, multiple endocrine adenomatosis type 2, and multiple endocrine neoplasia type 2 syndrome.

MEN2A      
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the parathyroid glands and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. An itchy skin condition may also occur. MEN2A is caused by a mutation (change) in a gene called RET. Also called MEN2A syndrome, multiple endocrine adenomatosis type 2A, multiple endocrine neoplasia type 2A syndrome, and Sipple syndrome.

MEN2A syndrome    listen   (... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the parathyroid glands and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. An itchy skin condition may also occur. MEN2A syndrome is caused by a mutation (change) in a gene called RET. Also called MEN2A, multiple endocrine adenomatosis type 2A, multiple endocrine neoplasia type 2A syndrome, and Sipple syndrome.

MEN2B      
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the adrenal glands and growths around the nerves in the lips, tongue, lining of the mouth, and eyelids. Gastrointestinal symptoms and trouble with the spine or bones in the feet and thighs may also occur. MEN2B is caused by a mutation (change) in a gene called RET. Also called MEN2B syndrome, multiple endocrine adenomatosis type 2B, and multiple endocrine neoplasia type 2B syndrome.

MEN2B syndrome    listen   (... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the adrenal glands and growths around the nerves in the lips, tongue, lining of the mouth, and eyelids. Gastrointestinal symptoms and trouble with the spine or bones in the feet and thighs may also occur. MEN2B syndrome is caused by a mutation (change) in a gene called RET. Also called MEN2B, multiple endocrine adenomatosis type 2B, and multiple endocrine neoplasia type 2B syndrome.

meningeal    listen   (meh-NIN-jee-ul)
Having to do with the meninges (three thin layers of tissue that cover and protect the brain and spinal cord).

meningeal carcinomatosis    listen   (meh-NIN-jee-ul KAR-sih-NOH-muh-TOH-sis)
A serious problem that may occur in cancer in which cancer cells spread from the original (primary) tumor to the meninges (thin layers of tissue that cover and protect the brain and spinal cord). It can happen in many types of cancer, but is the most common in melanoma, breast, lung, and gastrointestinal cancer. The cancer may cause the meninges to be inflamed. Also called carcinomatous meningitis, leptomeningeal carcinoma, leptomeningeal carcinomatosis, leptomeningeal metastasis, meningeal metastasis, and neoplastic meningitis.

meningeal leukemia    listen   (meh-NIN-jee-ul loo-KEE-mee-uh)
A serious problem that may occur in leukemia. In meningeal leukemia, cancer cells have spread from the original (primary) tumor to the meninges (thin layers of tissue that cover and protect the brain and spinal cord). The cancer may cause the meninges to be inflamed. Also called leukemic leptomeningitis and leukemic meningitis.

meningeal metastasis    listen   (meh-NIN-jee-ul meh-TAS-tuh-sis)
A serious problem that may occur in cancer in which cancer cells spread from the original (primary) tumor to the meninges (thin layers of tissue that cover and protect the brain and spinal cord). It can happen in many types of cancer, but is the most common in melanoma, breast, lung, and gastrointestinal cancer. The cancer may cause the meninges to be inflamed. Also called carcinomatous meningitis, leptomeningeal carcinoma, leptomeningeal carcinomatosis, leptomeningeal metastasis, meningeal carcinomatosis, and neoplastic meningitis.

meningeal syndrome    listen   (meh-NIN-jee-ul SIN-drome)
A condition marked by headache, fever, and a stiff neck, which is caused when the meninges (three thin layers of tissue that cover and protect the brain and spinal cord) become irritated. Meningeal syndrome may be caused by blood, cancer cells, or substances from the breakdown of cancer cells that get into the cerebrospinal fluid (CSF). It may also be caused by infection with a bacterium, virus, or fungus.

meninges    listen   (meh-NIN-jeez)
The three thin layers of tissue that cover and protect the brain and spinal cord.

meningioma    listen   (meh-NIN-jee-OH-muh)
A type of slow-growing tumor that forms in the meninges (thin layers of tissue that cover and protect the brain and spinal cord). Meningiomas usually occur in adults.

meningitis    listen   (MEH-nin-JY-tis)
Inflammation of the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). Meningitis is usually caused by a bacterial or viral infection, but sometimes is caused by cancer, drug allergies, or inflammatory diseases.

menopausal hormone therapy    listen   (MEH-nuh-PAW-zul HOR-mone THAYR-uh-pee)
Hormones (estrogen, progesterone, or both) given to women after menopause to replace the hormones no longer produced by the ovaries. Also called hormone replacement therapy and HRT.

menopause    listen   (MEH-nuh-pawz)
The time of life when a woman’s ovaries stop producing hormones and menstrual periods stop. Natural menopause usually occurs around age 50. A woman is said to be in menopause when she hasn’t had a period for 12 months in a row. Symptoms of menopause include hot flashes, mood swings, night sweats, vaginal dryness, trouble concentrating, and infertility.

menorrhagia    listen   (MEH-nuh-RAH-juh)
Abnormally heavy menstrual bleeding.

menstrual cycle    listen   (MEN-stroo-ul SY-kul)
The monthly cycle of hormonal changes from the beginning of one menstrual period to the beginning of the next.

menstrual period    listen   (MEN-stroo-ul PEER-ee-ud)
The periodic discharge of blood and tissue from the uterus. From puberty until menopause, menstruation occurs about every 28 days, but does not occur during pregnancy.

menstruation    listen   (MEN-stroo-WAY-shun)
Periodic discharge of blood and tissue from the uterus. From puberty until menopause, menstruation occurs about every 28 days when a woman is not pregnant.

mental health    listen   (MEN-tul helth)
A person’s overall psychological and emotional condition. Good mental health is a state of well-being in which a person is able to cope with everyday events, think clearly, be responsible, meet challenges, and have good relationships with others.

mental health counselor    listen   (MEN-tul helth KOWN-seh-ler)
A specialist who talks to patients and their families about emotional and personal matters, and can help them make decisions. Also called counselor.

menthol    listen   (MEN-thol)
A substance that comes from mint oils or is made in the laboratory. It is used to relieve itching and to treat problems in the upper respiratory tract. Menthol causes a cooling sensation when eaten or put on the skin and it acts as a mild pain killer. It is found in nasal sprays, cough drops, inhalers, creams, and lotions. It is also used as a flavor in many food and oral hygiene products.

MEPACT      
A drug being studied in the treatment of young adults with bone cancer that has gotten worse or come back. MEPACT activates certain types of white blood cells and helps the immune system kill cancer cells. It is a type of immunostimulant. Also called L-MTP-PE, mifamurtide, and muramyl tripeptide phosphatidylethanolamine.

meperidine hydrochloride    listen   (meh-PAYR-ih-deen HY-droh-KLOR-ide)
A drug used to treat moderate to severe pain. It binds to opioid receptors in the central nervous system. Meperidine hydrochloride is a type of analgesic agent and a type of opioid. Also called Demerol.

mercaptopurine    listen   (mer-KAP-toh-PYOOR-een)
A drug used to treat acute lymphoblastic leukemia. It may also be used to treat certain other conditions, such as Crohn disease and ulcerative colitis. Mercaptopurine stops cells from dividing and may kill cancer cells. It is a type of antimetabolite. Also called Purinethol and Purixan.

mercury    listen   (MER-kyoo-ree)
A silver-white, poisonous metal that is a liquid at ordinary temperatures. It is commonly used in thermometers and amalgams, and has been used as an ingredient in some homeopathic medicines and in very small amounts as a preservative in viral vaccines.

mercy killing    listen   (MER-see KIH-ling)
An easy or painless death, or the intentional ending of the life of a person suffering from an incurable or painful disease at his or her request. Also called euthanasia.

meridian    listen   (meh-RIH-dee-un)
In traditional Chinese medicine, one of 20 channels that form a network through which qi (the body's vital energy) flows and that connect the body’s acupuncture sites.

Merkel cell    listen   (MER-kul sel)
A special type of cell found right below the epidermis (top layer of skin). These cells are very close to the nerve endings that receive the sensation of touch and may be involved in touch. The cells also contain substances that may act as hormones.

Merkel cell cancer    listen   (MER-kul sel KAN-ser)
A rare type of cancer that forms on or just beneath the skin, usually in parts of the body that have been exposed to the sun. It is most common in older people and in people with weakened immune systems. Also called Merkel cell carcinoma, neuroendocrine carcinoma of the skin, and trabecular cancer.

Merkel cell carcinoma    listen   (MER-kul sel KAR-sih-NOH-muh)
A rare type of cancer that forms on or just beneath the skin, usually in parts of the body that have been exposed to the sun. It is most common in older people and in people with weakened immune systems. Also called Merkel cell cancer, neuroendocrine carcinoma of the skin, and trabecular cancer.

mesenchymal    listen   (meh-ZEN-kih-mul)
Refers to cells that develop into connective tissue, blood vessels, and lymphatic tissue.

mesenteric membrane    listen   (MEH-zen-TAYR-ik MEM-brayn)
The peritoneal membrane that attaches the intestines to the abdominal wall near the back.

mesna    listen   (MEZ-nuh)
A drug that helps protect the kidneys and bladder from the toxic effects of anticancer drugs such as ifosfamide and cyclophosphamide.

mesonephroma    listen   (MEH-zoh-neh-FROH-muh)
A rare type of tumor, usually of the female genital tract, in which the insides of the cells look clear when viewed under a microscope. Also called clear cell adenocarcinoma and clear cell carcinoma.

mesothelin    listen   (MEH-zoh-THEE-lin)
A protein found on the surface of certain types of normal cells and cancer cells. Mesothelin may help these cells stick together and send signals. A higher-than-normal amount of mesothelin is found on some cancer cells, including mesothelioma, pancreatic cancer, and ovarian cancer.

mesothelioma    listen   (MEH-zoh-THEE-lee-OH-muh)
A benign (not cancer) or malignant (cancer) tumor affecting the lining of the chest or abdomen. Exposure to asbestos particles in the air increases the risk of developing malignant mesothelioma.

messenger RNA    listen   (MEH-sen-jer …)
A type of RNA found in cells. Messenger RNA molecules carry the genetic information needed to make proteins. They carry the information from the DNA in the nucleus of the cell to the cytoplasm where the proteins are made. Also called mRNA.

MET tyrosine kinase inhibitor PF-02341066    listen   (… TY-ruh-seen KY-nays in-HIH-bih-ter …)
A drug used to treat advanced non-small cell lung cancer that has a mutated (changed) form of a gene called anaplastic lymphoma kinase (ALK). It is also being studied in the treatment of other types of cancer. MET tyrosine kinase inhibitor PF-02341066 blocks the protein made by the mutated ALK gene. Blocking this protein may stop the growth and spread of cancer cells. MET tyrosine kinase inhibitor PF-02341066 may also prevent the growth of new blood vessels that tumors need to grow. It is a type of tyrosine kinase inhibitor and a type of antiangiogenesis agent. Also called crizotinib, PF-02341066, and Xalkori.

MET/VEGFR-2 inhibitor GSK1363089    listen   (…. in-HIH-bih-ter ….)
A substance being studied in the treatment of cancer. MET/VEGFR-2 inhibitor GSK1363089 blocks enzymes involved in the growth and spread of tumor cells. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of tyrosine kinase inhibitor and a type of antiangiogenesis agent. Also called foretinib and XL880.

meta-analysis    listen   (meh-tuh-uh-NA-lih-sis)
A process that analyzes data from different studies done about the same subject. The results of a meta-analysis are usually stronger than the results of any study by itself.

metabolic    listen   (MEH-tuh-BAH-lik)
Having to do with metabolism (the total of all chemical changes that take place in a cell or an organism to produce energy and basic materials needed for important life processes).

metabolic acidosis    listen   (MEH-tuh-BAH-lik A-sih-DOH-sis)
A condition in which the blood is too acidic. It may be caused by severe illness or sepsis (bacteria in the bloodstream).

metabolic disorder    listen   (MEH-tuh-BAH-lik dis-OR-der)
A condition in which normal metabolic processes are disrupted, usually because of a missing enzyme.

metabolic syndrome    listen   (MEH-tuh-BAH-lik SIN-drome)
A condition marked by extra fat around the abdomen, high levels of blood glucose (sugar) when not eating, high levels of triglycerides (a type of fat) in the blood, low levels of high-density lipoproteins (a type of protein that carries fats) in the blood, and high blood pressure. People with metabolic syndrome are at increased risk of diabetes mellitus and diseases of the heart and blood vessels. Also called metabolic syndrome X.

metabolic syndrome X    listen   (MEH-tuh-BAH-lik SIN-drome ...)
A condition marked by extra fat around the abdomen, high levels of blood glucose (sugar) when not eating, high levels of triglycerides (a type of fat) in the blood, low levels of high-density lipoproteins (a type of protein that carries fats) in the blood, and high blood pressure. People with metabolic syndrome X are at increased risk of diabetes mellitus and diseases of the heart and blood vessels. Also called metabolic syndrome.

metabolic therapy    listen   (MEH-tuh-BAH-lik THAYR-uh-pee)
Treatment to correct changes in metabolism that can be caused by disease.

metabolic type    listen   (MEH-tuh-BAH-lik tipe)
In alternative medicine, a theory that people fall into one of three groups (protein, carbohydrate, or mixed type) based on the main type of food that their bodies need to stay healthy.

metabolism    listen   (meh-TA-buh-lih-zum)
The chemical changes that take place in a cell or an organism. These changes make energy and the materials cells and organisms need to grow, reproduce, and stay healthy. Metabolism also helps get rid of toxic substances.

metabolite    listen   (meh-TA-boh-lite)
A substance made or used when the body breaks down food, drugs or chemicals, or its own tissue (for example, fat or muscle tissue). This process, called metabolism, makes energy and the materials needed for growth, reproduction, and maintaining health. It also helps get rid of toxic substances.

metaiodobenzylguanidine scan    listen   (meh-tuh-I-oh-doh-BEN-zul-GWAH-nih-deen skan)
A procedure used to find neuroendocrine tumors, such as neuroblastomas and pheochromocytomas. A small amount of a substance called radioactive metaiodobenzylguanidine is injected into a vein and travels through the bloodstream. Neuroendocrine tumor cells take up the radioactive metaiodobenzylguanidine and are detected by a scanner. Also called iobenguane scan and MIBG scan.

metallic    listen   (meh-TA-lik)
Having to do with metal. Some cancer treatments may change the sense of taste and cause foods to have a metallic taste.

metallic endoprosthesis    listen   (meh-TA-lik EN-doh-pros-THEE-sis)
A device made of metal that is placed inside the body to replace a body part removed by surgery. An example is a thigh bone replaced during surgery for cancer.

metaplasia    listen   (meh-tuh-PLAY-zhuh)
A change of cells to a form that does not normally occur in the tissue in which it is found.

metaplastic carcinoma    listen   (meh-tuh-PLAS-tik KAR-sih-NOH-muh)
A general term used to describe cancer that begins in cells that have changed into another cell type (for example, a squamous cell of the esophagus changing to resemble a cell of the stomach). In some cases, metaplastic changes alone may mean there is an increased chance of cancer developing at the site.

metastasectomy    listen   (meh-TAS-tuh-SEK-toh-mee)
Surgery to remove one or more metastases (tumors formed from cells that have spread from the primary tumor). When all metastases are removed, it is called a complete metastasectomy.

metastasis    listen   (meh-TAS-tuh-sis)
The spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor. The plural form of metastasis is metastases (meh-TAS-tuh-SEEZ).

metastasize    listen   (meh-TAS-tuh-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.

metastatic    listen   (meh-tuh-STA-tik)
Having to do with metastasis, which is the spread of cancer from the primary site (place where it started) to other places in the body.

metasynchronous    listen   (meh-tuh-SING-kruh-nus)
Occurring at nearly the same time.

meteorism    listen   (MEE-tee-oh-rih-zum)
Swelling of the abdomen caused by gas in the intestines or peritoneal cavity. Also called tympanites.

metformin    listen   (met-FOR-min)
The active ingredient in a drug used to treat diabetes mellitus (a condition in which the body cannot control the level of sugar in the blood). It is also being studied in the treatment of cancer. It decreases the amount of glucose (a type of sugar) released into the bloodstream from the liver and increases the body’s use of the glucose. Metformin is a type of antidiabetic agent.

metformin hydrochloride    listen   (met-FOR-min HY-droh-KLOR-ide)
A drug used to treat diabetes mellitus (a condition in which the body cannot control the level of sugar in the blood ). It is also being studied in the treatment of cancer. It decreases the amount of glucose (a type of sugar) released into the bloodstream from the liver and increases the body’s use of the glucose. Metformin hydrochloride is a type of antidiabetic agent. Also called Glucophage.

methadone hydrochloride    listen   (MEH-thuh-DONE HY-droh-KLOR-ide)
A drug used to treat moderate to severe pain that does not respond to other types of pain medicine. It is also used to help people who are addicted to opioid drugs such as heroin. Methadone hydrochloride binds to opioid receptors in the central nervous system. It is a type of analgesic agent and a type of opioid.

methanol    listen   (MEH-thuh-nol)
A type of alcohol used to make antifreeze, pesticides, windshield wiper fluid, paint thinner, certain types of fuel, and other substances. Methanol catches fire easily and is very poisonous. It is one of many harmful chemicals found in tobacco smoke. Also called methyl alcohol and wood alcohol.

methemoglobin    listen   (met-HEE-moh-GLOH-bin)
A form of hemoglobin found in the blood in small amounts. Unlike normal hemoglobin, methemoglobin cannot carry oxygen. Injury or certain drugs, chemicals, or foods may cause a higher-than-normal amount of methemoglobin to be made. This causes a condition called methemoglobinemia.

methemoglobinemia    listen   (MET-hee-moh-GLOH-bih-NEE-mee-uh)
A condition in which a higher-than-normal amount of methemoglobin is found in the blood. Methemoglobin is a form of hemoglobin that cannot carry oxygen. In methemoglobinemia, tissues cannot get enough oxygen. Symptoms may include headache, dizziness, fatigue, shortness of breath, nausea, vomiting, rapid heartbeat, loss of muscle coordination, and blue-colored skin. Methemoglobinemia can be caused by injury or being exposed to certain drugs, chemicals, or foods. It can also be an inherited condition.

methodology    listen   (MEH-thuh-DAH-loh-jee)
In medicine, the rules and procedures for doing research and evaluating results.

methotrexate    listen   (meh-thuh-TREK-sayt)
A drug used to treat some types of cancer, rheumatoid arthritis, and severe skin conditions, such as psoriasis. Methotrexate stops cells from making DNA and may kill cancer cells. It is a type of antimetabolite. Also called amethopterin, MTX, and Rheumatrex.

methoxsalen    listen   (meh-THOK-suh-len)
A drug used together with UV light to treat psoriasis, vitiligo, and skin nodules of cutaneous T-cell lymphoma. It is also being studied in the treatment of graft-versus-host disease. It belongs to the family of drugs called psoralens and furocoumarins.

methoxyamine hydrochloride    listen   (meh-THOK-see-uh-meen HY-droh-KLOR-ide)
A substance being studied in the treatment of cancer. It blocks the ability of a cell to repair damage to its DNA and may kill cancer cells. It may also help some anticancer drugs work better. It is a type of antineoplastic agent.

methoxypolyethylene glycol epoetin beta    listen   (meh-THOK-see-PAH-lee-EH-thih-leen GLY-kol ee-POH-eh-tin BAY-tuh)
A substance being studied in the treatment of anemia in patients who are receiving chemotherapy. It is a form of erythropoietin (a substance produced in the kidneys that stimulates the production of red blood cells) that has been changed in the laboratory. Also called Ro 50-3821.

methyl alcohol    listen   (MEH-thul AL-kuh-hol)
A type of alcohol used to make antifreeze, pesticides, windshield wiper fluid, paint thinner, certain types of fuel, and other substances. Methyl alcohol catches fire easily and is very poisonous. It is one of many harmful chemicals found in tobacco smoke. Also called methanol and wood alcohol.

methyl group    listen   (MEH-thul groop)
A small molecule made of one carbon and three hydrogen atoms. Methyl groups are added or removed from proteins or nucleic acids and may change the way these molecules act in the body.

methyl-5-aminolevulinate    listen   (MEH-thul-5-uh-MEE-noh-LEH-vyoo-LIH-nayt)
A drug used in photodynamic therapy; it is absorbed by tumor cells and, when exposed to light, becomes active and kills the cancer cells.

methylation    listen   (MEH-thuh-LAY-shun)
A chemical reaction in which a small molecule called a methyl group is added to other molecules. Methylation of proteins or nucleic acids may affect how they act in the body.

methylnaltrexone    listen   (MEH-thul-nal-TREK-sone)
The active ingredient in a drug used to relieve certain side effects caused by treatment with opiods (pain killers similar to morphine), such as constipation (hard, dry stools), itching, and low urine flow. Methylnaltrexone binds to opioid receptors outside the brain and may block the side effects of opioid drugs without affecting their ability to relieve pain. Methylnaltrexone is a type of peripheral opioid receptor antagonist.

methylnaltrexone bromide    listen   (MEH-thul-nal-TREK-sone BROH-mide)
A drug used to relieve certain side effects caused by treatment with opiods (pain killers similar to morphine), such as constipation (hard, dry stools), itching, and low urine flow. Methylnaltrexone bromide binds to opioid receptors outside the brain and may block the side effects of opioid drugs without affecting their ability to relieve pain. Methylnaltrexone bromide is a type of peripheral opioid receptor antagonist. Also called Relistor.

methylphenidate hydrochloride    listen   (MEH-thul-feh-NIH-dayt HY-droh-KLOR-ide)
A drug used to treat certain behavior disorders, such as attention deficit hyperactivity disorder (ADHD). It is also being studied as a way to improve brain function in patients treated with anticancer drugs. Methylphenidate hydrochloride acts on certain parts of the brain. It is a type of central nervous system stimulant. Also called Concerta and Ritalin.

methylprednisolone    listen   (MEH-thul-pred-NIH-suh-lone)
A corticosteroid hormone replacement.

metoclopramide    listen   (meh-toh-KLOH-pruh-mide)
A drug that increases the motility (movements and contractions) of the stomach and upper intestine. It is used to treat certain stomach problems and nausea and vomiting caused by chemotherapy. It is a type of antiemetic and a type of motility agent. Also called Reglan.

metronidazole    listen   (MEH-troh-NY-duh-zole)
A drug that is used to treat infection and is being studied in the treatment of cancer. It is a type of antibacterial, antiprotozoal, and anthelmintic. Also called Flagyl.

metronomic therapy    listen   (MEH-truh-NAH-mik THAYR-uh-pee)
Continuous or frequent treatment with low doses of anticancer drugs, often given with other methods of therapy.

MeV linear accelerator    listen   (... LIH-nee-er ak-SEH-leh-RAY-ter)
A machine that uses electricity to form a stream of fast-moving subatomic particles. This creates high-energy radiation that may be used to treat cancer. Also called linac, linear accelerator, and mega-voltage linear accelerator.

Mevacor    listen   (MEH-vuh-kor)
A drug used to lower the amount of cholesterol in the blood. It is also being studied in the prevention and treatment of some types of cancer. Mevacor is a type of HMG-CoA reductase inhibitor (statin). Also called lovastatin.

mevalonate pathway    listen   (meh-VA-loh-nayt PATH-way)
Describes a series of reactions in which proteins work together to make molecules. These molecules are part of many processes, including making cholesterol. Changes in this pathway may lead to cancer cell growth. Drugs or substances that affect this pathway are used to treat high cholesterol, and are being studied in the prevention and treatment of cancer and other diseases.

Mexican valerian    listen   (MEK-sih-kun vuh-LEER-ee-un)
A plant whose roots are used as a sedative and to treat certain medical conditions. It is being studied as a way to improve sleep in cancer patients undergoing treatment. Also called garden heliotrope, garden valerian, Indian valerian, Pacific valerian, valerian, Valeriana officinalis, and Valerianae radix.

mFOLFOX-6    listen  
An abbreviation for a combination chemotherapy regimen that is used to treat colorectal cancer. It includes the drugs leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin. There are several different FOLFOX regimens that differ in the doses and ways in which the three drugs are given. Also called mFOLFOX-6 regimen, modified FOLFOX-6, and modified FOLFOX-6 regimen.

mFOLFOX-6 regimen    listen   (... REH-jih-men)
An abbreviation for a combination chemotherapy regimen that is used to treat colorectal cancer. It includes the drugs leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin. There are several different FOLFOX regimens that differ in the doses and ways in which the three drugs are given. Also called mFOLFOX-6, modified FOLFOX-6, and modified FOLFOX-6 regimen.

MG98      
A substance being studied in the treatment of cancer. It blocks the production of a protein called DNA methyltransferase, which helps control gene expression. This may kill cancer cells that need DNA methyltransferase to grow. It is a type of antisense oligonucleotide.

MGCD0103      
A substance being studied in the treatment of several types of cancer. It blocks enzymes needed for cell division and may kill cancer cells. It is a type of histone deacetylase (HDAC) inhibitor. Also called mocetinostat.

MGUS      
A benign condition in which there is a higher-than-normal level of a protein called M protein in the blood. Patients with MGUS are at an increased risk of developing cancer. Also called monoclonal gammopathy of undetermined significance.

MIBG scan    listen   (... skan)
A procedure used to find neuroendocrine tumors, such as neuroblastomas and pheochromocytomas. A small amount of a substance called radioactive MIBG is injected into a vein and travels through the bloodstream. Neuroendocrine tumor cells take up the radioactive MIBG and are detected by a scanner. Also called iobenguane scan and metaiodobenzylguanidine scan.

micelle    listen   (MY-sel)
A tiny particle made of substances that are soluble in water and that come together to form a ball-like shape. These particles can carry other substances inside them. In medicine, micelles are made in the laboratory and are used to carry drugs to body tissues and cells.

microarray    listen   (MY-kroh-uh-RAY)
A laboratory tool used to analyze large numbers of genes or proteins at one time. In a microarray, biologic molecules such as DNA, RNA, or protein are placed in a pattern onto a surface such as a glass slide. Other substances are added to these slides to detect specific patterns of molecules. Microarrays are being used to help diagnose diseases, such as cancer, and to develop treatments for them.

microbicide    listen   (my-KROH-bih-side)
Any substance or process that kills germs (bacteria, viruses, and other microorganisms that can cause infection and disease). Also called germicide.

microbiome    listen   (MY-kroh-BY-ome)
The collection of all the microorganisms and viruses that live in a given environment, including the human body or part of the body, such as the digestive system. The human microbiome may play a role in a person’s health. Studying the human microbiome may help prevent and treat disease in the future.

microcalcification    listen   (MY-kroh-KAL-sih-fih-KAY-shun)
A tiny deposit 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.

microflora    listen   (MY-kroh-FLOR-uh)
Bacteria and other organisms that live inside the intestines. They help digest food. Vitamins such as biotin and vitamin K are made by microflora. Also called gut flora, gut microflora, intestinal flora, and intestinal microflora.

microfluidic device    listen   (MY-kroh-floo-IH-dik dee-VISE)
An instrument that uses very small amounts of fluid on a microchip to do certain laboratory tests. A microfluidic device may use body fluids or solutions containing cells or cell parts to diagnose diseases. Also called lab-on-a-chip.

microgram    listen   (MY-kroh-gram)
One millionth of a gram.

microliter    listen   (MY-kroh-LEE-ter)
A measure of volume for a liquid, using the metric system. One microliter is equal to a millionth of a liter. Also called µL.

micrometastasis    listen   (MY-kroh-meh-TAS-tuh-sis)
Small numbers of cancer cells that have spread from the primary tumor to other parts of the body and are too few to be picked up in a screening or diagnostic test.

micromolar    listen   (MY-kroh-MOH-ler)
A concentration of 1/1,000,000 (one millionth) molecular weight per liter (mol/L).

micromole    listen   (MY-kroh-mole)
The amount of a substance equal to a millionth of a mole (a measure of the amount of a substance). Also called µM.

micronutrient    listen   (MY-kroh-NOO-tree-ent)
A substance the body needs in tiny amounts to grow and stay healthy. Examples are vitamins and minerals.

microorganism    listen   (MY-kroh-OR-guh-NIH-zum)
An organism that can be seen only through a microscope. Microorganisms include bacteria, protozoa, algae, and fungi. Although viruses are not considered living organisms, they are sometimes classified as microorganisms.

microRNA    listen   (MY-kroh …)
A type of RNA found in cells and in blood. MicroRNAs are smaller than many other types of RNA and can bind to messenger RNAs (mRNAs) to block them from making proteins. MicroRNAs are being studied in the diagnosis and treatment of cancer. Also called miRNA.

microsatellite    listen   (MY-kroh-SA-teh-lite)
A short sequence of DNA, usually 1 to 4 basepairs (a unit of DNA), that is repeated together in a row along the DNA molecule. There is variation from person to person in the number of repeats. There are hundreds of places in human DNA that contain microsatellites.

microsatellite instability    listen   (MY-kroh-SA-teh-lite in-stuh-BIH-lih-tee)
A change that occurs in the DNA of certain cells (such as tumor cells) in which the number of repeats of microsatellites (short, repeated sequences of DNA) is different than the number of repeats that was in the DNA when it was inherited. The cause of microsatellite instability may be a defect in the ability to repair mistakes made when DNA is copied in the cell. Also called MSI.

microscope    listen   (MY-kroh-SKOPE)
An instrument that is used to look at cells and other small objects that cannot be seen with the eye alone.

microscopic    listen   (MY-kroh-SKAH-pik)
Too small to be seen without a microscope.

microsphere    listen   (MY-kroh-sfeer)
A very tiny, hollow, round particle made from glass, ceramic, plastic, or other materials. Microspheres injected into blood vessels that feed a tumor may kill the tumor by blocking its blood supply. They can also be filled with a substance that may help kill more tumor cells.

microstaging    listen   (MY-kroh-STAY-jing)
A technique used to help determine the stage (extent) of melanoma and certain squamous cell cancers. A sample of skin that contains tumor tissue is examined under a microscope to find out how thick the tumor is and/or how deeply the tumor has grown into the skin or connective tissues.

microwave acupuncture    listen   (MY-kroh-WAYV AK-yoo-PUNK-cher)
A type of acupuncture in which a microwave device is attached to an acupuncture needle to give microwave radiation at an acupuncture point.

microwave therapy    listen   (MY-kroh-WAYV THAYR-uh-pee)
A type of treatment in which body tissue is exposed to high temperatures to damage and kill cancer cells or to make cancer cells more sensitive to the effects of radiation and certain anticancer drugs. Also called microwave thermotherapy.

microwave thermotherapy    listen   (MY-kroh-WAYV THER-moh-THAYR-uh-pee)
A type of treatment in which body tissue is exposed to high temperatures to damage and kill cancer cells or to make cancer cells more sensitive to the effects of radiation and certain anticancer drugs. Also called microwave therapy.

midazolam    listen   (mih-DAY-zoh-lam)
A drug used to treat anxiety and tension and to relax muscles. It is also being studied in the treatment of nausea and vomiting caused by some cancer treatments. It is a type of benzodiazepine. Also called midazolam hydrochloride and Versed.

midazolam hydrochloride    listen   (mih-DAY-zoh-lam HY-droh-KLOR-ide)
A drug used to treat anxiety and tension and to relax muscles. It is also being studied in the treatment of nausea and vomiting caused by some cancer treatments. It is a type of benzodiazepine. Also called midazolam and Versed.

midostaurin    listen   (MY-doh-STAW-rin)
A substance that is being studied in the treatment of leukemia. It belongs to the family of drugs called protein kinase inhibitors. Also called N-benzoyl-staurosporine and PKC412.

mifamurtide    listen   (mih-FAM-yoor-tide)
A drug being studied in the treatment of young adults with bone cancer that has gotten worse or come back. Mifamurtide activates certain types of white blood cells and helps the immune system kill cancer cells. It is a type of immunostimulant. Also called L-MTP-PE, MEPACT, and muramyl tripeptide phosphatidylethanolamine.

Mifeprex    listen   (MIH-feh-PREX)
A drug used to end early pregnancies. It is also being studied in the treatment of some types of cancer and other conditions. Mifeprex blocks the action of progesterone, a hormone that helps some cancers grow. It is a type of antiprogesterone. Also called mifepristone and RU 486.

mifepristone    listen   (MIH-feh-PRIS-tone)
A drug used to end early pregnancies. It is also being studied in the treatment of some types of cancer and other conditions. Mifepristone blocks the action of progesterone, a hormone that helps some cancers grow. It is a type of antiprogesterone. Also called Mifeprex and RU 486.

milatuzumab    listen   (MIH-luh-TOO-zoo-mab)
A substance being studied in the treatment of multiple myeloma and several other types of cancer. It binds to CD74, a protein on the surface of myeloma cells and certain other types of cells. It may help kill cancer cells. Milatuzumab is a type of monoclonal antibody. Also called hLL1 and IMMU-110.

milk duct    listen   (... dukt)
A thin tube in the breast that carries milk from the breast lobules to the nipple. Also called breast duct.

milk thistle    listen   (milk THIH-sul)
A plant that has been used in some cultures to treat certain medical problems, including stomach, liver, and gallbladder disorders. The active extract of milk thistle seeds is called silymarin. It is being studied in the prevention of liver damage caused by some cancer treatments. Also called Silybum marianum.

milligram    listen   (MIH-lih-gram)
A measure of weight. A milligram is approximately 450,000 times smaller than a pound and 28,000 times smaller than an ounce.

milliliter    listen   (MIH-luh-LEE-ter)
A measure of volume in the metric system. One thousand milliliters equal one liter. Also called cc, cubic centimeter, and ml.

millimeter    listen   (MIH-luh-MEE-ter)
A measure of length in the metric system. A millimeter is one thousandth of a meter. There are 25 millimeters in an inch.

millimole    listen   (MIH-lih-mole)
The amount of a substance equal to a thousandth of a mole (a measure of the amount of a substance). Also called mM.

mind-body exercise    listen   (mind-BAH-dee EK-ser-SIZE)
A form of exercise that combines body movement, mental focus, and controlled breathing to improve strength, balance, flexibility, and overall health. Examples of mind-body exercises are yoga, tai chi, and qigong.

mind-body modality    listen   (mind-BAH-dee moh-DA-lih-tee)
A health practice that combines mental focus, controlled breathing, and body movements to help relax the body and mind. It may be used to help control pain, stress, anxiety, and depression, and for overall health. Examples of mind-body modalities include meditation, hypnosis, guided imagery, yoga, and tai chi. A mind-body modality is a type of complementary and alternative medicine. Also called mind-body practice.

mind-body practice    listen   (mind-BAH-dee PRAK-tis)
A health practice that combines mental focus, controlled breathing, and body movements to help relax the body and mind. It may be used to help control pain, stress, anxiety, and depression, and for overall health. Examples of mind-body practices include meditation, hypnosis, guided imagery, yoga, and tai chi. A mind-body practice is a type of complementary and alternative medicine. Also called mind-body modality.

mindfulness relaxation    listen   (... ree-lak-SAY-shun)
A type of meditation based on the concept of being “mindful,” or having increased awareness, of the present. It uses breathing methods, guided imagery, and other practices to relax the body and mind and help reduce stress.

mineral    listen   (MIH-neh-rul)
In medicine, a mineral is a nutrient that is needed in small amounts to keep the body healthy. Mineral nutrients include the elements calcium, magnesium, and iron.

mineral oil    listen   (MIH-neh-rul oyl)
A type of oil that is made from petroleum (mixture of oily liquids found in the earth). Mineral oil is used in laxatives, lubricants, creams, and lotions.

minimal sedation    listen   (MIH-nih-mul seh-DAY-shun)
A level of sedation in which a person is very relaxed and may be awake. The person is able to answer questions and follow instructions. Minimal sedation is caused by special drugs and is used to help relieve anxiety during certain medical or surgical procedures. Also called anxiolysis.

minimally invasive surgery    listen   (MIH-nih-muh-lee in-VAY-siv SER-juh-ree)
Surgery that is done using small incisions (cuts) and few stitches. During minimally invasive surgery, one or more small incisions may be made in the body. A laparoscope (thin, tube-like instrument with a light and a lens for viewing) is inserted through one opening to guide the surgery. Tiny surgical instruments are inserted through other openings to do the surgery. Minimally invasive surgery may cause less pain, scarring, and damage to healthy tissue, and the patient may have a faster recovery than with traditional surgery.

minocycline-EDTA    listen   (mih-noh-SY-kleen ...)
A substance being studied in the prevention of bacterial infections that occur in catheters (thin tubes that carry fluids into or out of the body). It is a combination of minocycline, an antibiotic that blocks the growth of bacteria, and EDTA, a substance that keeps blood clots from forming. Minocycline-EDTA removes metals that bacteria use to form biofilms (thin layers stuck to surfaces). Also called M-EDTA.

MIP test    listen   (… test)
A test that measures the strength of the muscles used in breathing. A person inhales and exhales through a device called a manometer, and the pressures are recorded by a computer. Also called maximum inspiratory pressure test.

Miraluma test    listen   (meer-uh-LOO-muh ...)
A type of breast imaging test that is used to detect cancer cells in the breasts of some women who have had abnormal mammograms, or who have dense breast tissue. It is not used for screening or in place of a mammogram. In this test, a woman receives an injection of a small amount of a radioactive substance called technetium 99, which is taken up by cancer cells, and a gamma camera is used to take pictures of the breasts. Also called scintimammography and sestamibi breast imaging.

miRNA      
A type of RNA found in cells and in blood. miRNA are smaller than many other types of RNA and can bind to messenger RNAs (mRNAs) to block them from making proteins. miRNA are being studied in the diagnosis and treatment of cancer. Also called microRNA.

mirtazapine    listen   (mir-TA-zuh-peen)
A drug used to treat depression. Mirtazapine increases the levels of the chemicals serotonin and norepinephrine in the brain, which helps improve mood. It is a type of antidepressant. Also called Remeron.

misoprostol    listen   (MY-soh-PROS-tole)
A radioprotective agent that belongs to the family of drugs called prostaglandins.

mistletoe    listen   (MIH-sul-toh)
A semiparasitic plant that grows on some types of trees. Mistletoe extracts are being studied as treatments for cancer.

mistletoe lectin    listen   (MIH-sul-toh LEK-tin)
A substance that comes from the mistletoe plant and that is being studied as a treatment for cancer. A lectin is a complex molecule that has both protein and sugars. Lectins are able to bind to the outside of a cell and cause biochemical changes in it. Lectins are made by both animals and plants.

Mithracin    listen   (MITH-ruh-sin)
A drug used to treat some types of testicular cancer. It is also used to treat a higher-than-normal amounts of calcium in the blood or urine. Mithracin binds to DNA and prevents cells from making RNA and proteins. It is a type of antineoplastic antibiotic. Also called mithramycin and plicamycin.

mithramycin    listen   (MITH-ruh-MY-sin)
A drug used to treat some types of testicular cancer. It is also used to treat a higher-than-normal amounts of calcium in the blood or urine. Mithramycin binds to DNA and prevents cells from making RNA and proteins. It is a type of antineoplastic antibiotic. Also called Mithracin and plicamycin.

mitigate    listen   (MIH-tih-gayt)
To make milder or less painful.

mitochondria    listen   (MY-toh-KON-dree-uh)
Small structures in a cell that are found in the cytoplasm (fluid that surrounds the cell nucleus). Mitochondria make most of the energy for the cell and have their own genetic material that is different from the genetic material found in the nucleus. Many diseases are caused by mutations (changes) in the DNA of mitochondria. Mitochondria are cell organelles.

mitoguazone dihydrochloride    listen   (MY-toh-gwah-ZONE dy-HY-droh-KLOR-ide)
A substance being studied in the treatment of some leukemias and lymphomas. It blocks the growth of cells and may cause cancer cells to die. It is a type of polyamine synthesis inhibitor.

mitolactol    listen   (MY-toh-LAK-tole)
An anticancer drug that belongs to the family of drugs called alkylating agents.

mitomycin C    listen   (MY-toh-MY-sin ...)
A drug used to treat advanced cancer of the stomach and pancreas that has not gotten better with other treatment. It is also being studied in the treatment of other types of cancer. Mitomycin C comes from bacteria. It damages the cell’s DNA and may kill cancer cells. It is a type of anticancer antibiotic. Also called Mitozytrex and Mutamycin.

mitosis    listen   (my-TOH-sis)
The process by which a single parent cell divides to make two new daughter cells. Each daughter cell receives a complete set of chromosomes from the parent cell. This process allows the body to grow and replace cells.

mitotane    listen   (MY-toh-tane)
An anticancer drug used in treating adrenocortical cancer and ACTH-producing pituitary tumors (Cushing disease).

mitotic activity    listen   (my-TAH-tik ak-TIH-vih-tee)
Having to do with the presence of dividing (proliferating) cells. Cancer tissue generally has more mitotic activity than normal tissues.

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

mitotic index    listen   (my-TAH-tik IN-dex)
In a population of cells, the ratio of the number of cells undergoing mitosis (cell division) to the number of cells not undergoing mitosis.

mitotic inhibitor    listen   (my-TAH-tik in-HIH-bih-ter)
A type of drug that blocks cell growth by stopping mitosis (cell division). They are used to treat cancer. Also called antimitotic agent.

mitotic rate    listen   (my-TAH-tik rayt)
A measure of how fast cancer cells are dividing and growing. To find the mitotic rate, the number of cells dividing in a certain amount of cancer tissue is counted. Mitotic rate is used to help find the stage of melanoma (a type of skin cancer) and other types of cancer. Higher mitotic rates are linked with lower survival rates. Also called MR.

mitoxantrone    listen   (MY-toh-ZAN-trone)
A drug used to treat advanced prostate cancer that does not respond to hormones, adult acute nonlymphocytic leukemia, and advanced or chronic multiple sclerosis. It is also being studied in the treatment of other cancers. It belongs to the family of drugs called antitumor antibiotics. Also called Novantrone.

Mitozytrex    listen   (MY-toh-ZY-trex)
A drug used to treat advanced cancer of the stomach and pancreas that has not gotten better with other treatment. It is also being studied in the treatment of other types of cancer. Mitozytrex comes from bacteria. It damages the cell’s DNA and may kill cancer cells. It is a type of anticancer antibiotic. Also called mitomycin C and Mutamycin.

mivobulin isethionate    listen   (MY-voh-BYOO-lin I-seh-THY-oh-nayt)
An anticancer drug that belongs to the family of drugs called mitotic inhibitors. Also called CI-980.

mixed glioma    listen   (mikst glee-OH-muh)
A brain tumor that forms from more than one type of brain cell, usually astrocytes and oligodendrocytes.

MK-0646      
A substance being studied in the treatment of many types of cancer. MK-0646 binds to a protein called insulin-like growth factor receptor (IGFR) on the surface of cells. This may prevent the cells from growing when IGF is present. It may also kill cancer cells. MK-0646 is a type of monoclonal antibody. Also called anti-IGF1R recombinant monoclonal antibody MK-0646.

MK0752      
A substance being studied in the treatment of cancer. It blocks signals between growing cells and may kill cancer cells. It is a type of signal transduction inhibitor.

ml    listen  
A measure of volume in the metric system. One thousand mls equal one liter. Also called cc, cubic centimeter, and milliliter.

MLN1202      
A substance being studied as a treatment for atherosclerosis (a build-up of fat in the arteries). It is also being studied in the treatment of cancers that spread to the bone. MLN1202 binds to a protein called CCR2, which is found on the surface of certain bone cells, white blood cells, and cancer cells. MLN1202 blocks the action of a substance that is involved in keeping healthy bone mass. It may help keep the cancer cells from spreading to and growing in the bone. It is a type of monoclonal antibody. Also called anti-CCR2 monoclonal antibody MLN1202.

MLN2704      
A substance that is being studied in the treatment of prostate cancer. It belongs to the family of drugs called antibody drug conjugates. Also called MLN591DM1.

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

MLN591DM1      
A substance that is being studied in the treatment of prostate cancer. It belongs to the family of drugs called antibody drug conjugates. Also called MLN2704.

mM    listen  
The amount of a substance equal to a thousandth of a mole (a measure of the amount of a substance). Also called millimole.

MMMT      
A rare type of tumor that is a mixture of carcinoma and sarcoma cells. MMMT usually occurs in the uterus. Also called malignant mixed Müllerian tumor.

MOAB Ch14.18      
A substance being studied in the treatment of cancer. It binds to a molecule called GD2, which is found in greater than normal amounts on some types of cancer cells. This helps cells of the immune system kill the cancer cells. It is a type of monoclonal antibody. Also called Ch14.18 and monoclonal antibody Ch14.18.

MoAb HuM195      
A substance being studied in the treatment of myelodysplastic syndromes and some types of leukemia. It binds to CD33, a protein on the surface of certain normal blood stem cells and some abnormal blood cells. It causes the immune system to kill these cells. MoAb HuM195 is a type of monoclonal antibody. Also called lintuzumab and monoclonal antibody HuM195.

mocetinostat    listen   (MOH-seh-TIH-noh-stat)
A substance being studied in the treatment of several types of cancer. It blocks enzymes needed for cell division and may kill cancer cells. It is a type of histone deacetylase (HDAC) inhibitor. Also called MGCD0103.

modafinil    listen   (moh-DA-fih-nil)
A drug that is being studied as a treatment for fatigue in patients with cancer. It belongs to the family of drugs called stimulants.

modality    listen   (moh-DA-lih-tee)
A method of treatment. For example, surgery and chemotherapy are treatment modalities.

moderate sedation    listen   (MAH-deh-rut seh-DAY-shun)
A level of sedation in which a person is asleep but wakes when spoken to or touched. Moderate sedation is caused by special drugs and is used to help relieve anxiety during certain medical or surgical procedures. Drugs that relieve pain may be given at the same time. Also called conscious sedation.

modified FOLFOX-6    listen   (MAH-dih-FIDE ...)
An abbreviation for a combination chemotherapy regimen that is used to treat colorectal cancer. It includes the drugs leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin. There are several different FOLFOX regimens that differ in the doses and ways in which the three drugs are given. Also called mFOLFOX-6, mFOLFOX-6 regimen, and modified FOLFOX-6 regimen.

modified FOLFOX-6 regimen    listen   (MAH-dih-FIDE ... REH-jih-men)
An abbreviation for a combination chemotherapy regimen that is used to treat colorectal cancer. It includes the drugs leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin. There are several different FOLFOX regimens that differ in the doses and ways in which the three drugs are given. Also called mFOLFOX-6, mFOLFOX-6 regimen, and modified FOLFOX-6.

modified radical mastectomy    listen   (MAH-dih-FIDE RA-dih-kul ma-STEK-toh-mee)
Surgery for breast cancer in which the breast, most or all of the lymph nodes under the arm, and the lining over the chest muscles are removed. Sometimes the surgeon also removes part of the chest wall muscles.

modified radical vulvectomy    listen   (MAH-dih-FIDE RA-dih-kul vul-VEK-toh-mee)
Surgery to remove most, but not all, of the vulva (the external female genital organs, including the clitoris, vaginal lips, and the opening to the vagina). The clitoris may not be removed. Sometimes lymph nodes in the groin area are also removed. Also called partial radical vulvectomy.

modulate    listen   (MAH-juh-layt)
To adjust, or change.

Mohs micrographic surgery    listen   (moze MY-kroh-GRA-fik SER-juh-ree)
A surgical procedure used to treat skin cancer. Individual layers of cancer tissue are removed and examined under a microscope one at a time until all cancer tissue has been removed. Also called Mohs surgery.

Mohs surgery    listen   (moze SER-juh-ree)
A surgical procedure used to treat skin cancer. Individual layers of cancer tissue are removed and examined under a microscope one at a time until all cancer tissue has been removed. Also called Mohs micrographic surgery.

molar pregnancy    listen   (MOH-ler PREG-nun-see)
A slow-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta) after fertilization of an egg by a sperm. A molar pregnancy contains many cysts (sacs of fluid). It is usually benign (not cancer) but it may spread to nearby tissues (invasive mole). It may also become a malignant tumor called choriocarcinoma. Molar pregnancy is the most common type of gestational trophoblastic tumor. Also called hydatidiform mole.

mold    listen   (mold)
A form of fungus. Some molds can cause disease in humans.

mole    listen   (mole)
A benign (not cancer) growth on the skin that is formed by a cluster of melanocytes (cells that make a substance called melanin, which gives color to skin and eyes). A mole is usually dark and may be raised from the skin. Also called nevus.

molecular diagnosis    listen   (muh-LEH-kyoo-ler dy-ug-NOH-sis)
The process of identifying a disease by studying molecules, such as proteins, DNA, and RNA, in a tissue or fluid.

molecular marker    listen   (muh-LEH-kyoo-ler MAR-ker)
A biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease. A molecular marker may be used to see how well the body responds to a treatment for a disease or condition. Also called biomarker and signature molecule.

molecular mass    listen   (muh-LEH-kyoo-ler mas)
The sum of the atomic masses of all atoms in a molecule, based on a scale in which the atomic masses of hydrogen, carbon, nitrogen, and oxygen are 1, 12, 14, and 16, respectively. For example, the molecular mass of water, which has two atoms of hydrogen and one atom of oxygen, is 18 (i.e., 2 + 16). Also called molecular weight.

molecular medicine    listen   (muh-LEH-kyoo-ler MEH-dih-sin)
A branch of medicine that develops ways to diagnose and treat disease by understanding the way genes, proteins, and other cellular molecules work. Molecular medicine is based on research that shows how certain genes, molecules, and cellular functions may become abnormal in diseases such as cancer.

molecular pathway    listen   (muh-LEH-kyoo-ler …)
A series of actions among molecules in a cell that leads to a certain end point or cell function.

molecular risk assessment    listen   (muh-LEH-kyoo-ler risk uh-SES-ment)
A procedure in which biomarkers (for example, biological molecules or changes in tumor cell DNA) are used to estimate a person’s risk for developing cancer. Specific biomarkers may be linked to particular types of cancer.

molecular weight    listen   (muh-LEH-kyoo-ler wayt)
The sum of the atomic masses of all atoms in a molecule, based on a scale in which the atomic masses of hydrogen, carbon, nitrogen, and oxygen are 1, 12, 14, and 16, respectively. For example, the molecular weight of water, which has two atoms of hydrogen and one atom of oxygen, is 18 (i.e., 2 + 16). Also called molecular mass.

molecularly targeted therapy    listen   (muh-LEH-kyoo-ler-lee TAR-geh-ted THAYR-uh-pee)
In cancer treatment, substances that kill cancer cells by targeting key molecules involved in cancer cell growth.

molecule    listen   (MAH-leh-kyool)
The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.

mometasone    listen   (moh-MEH-tuh-sone)
A drug that is used in a cream to treat certain skin conditions and in a nasal spray to treat sinus problems caused by allergies. It is being studied as a way to treat inflammation of the skin caused by radiation therapy. Mometasone is a type of corticosteroid. Also called Elocon, mometasone furoate, and Nasonex.

mometasone furoate    listen   (moh-MEH-tuh-sone FYOOR-oh-ayt)
A drug that is used in a cream to treat certain skin conditions and in a nasal spray to treat sinus problems caused by allergies. It is being studied as a way to treat inflammation of the skin caused by radiation therapy. Mometasone furoate is a type of corticosteroid. Also called Elocon, mometasone, and Nasonex.

monitor    listen   (MAH-nih-ter)
In medicine, to regularly watch and check a person or condition to see if there is any change. Also refers to a device that records and/or displays patient data, such as for an electrocardiogram (EKG).

monk’s pepper    listen   (munks PEH-per)
An extract made from the fruit of the chaste tree (Vitex agnus-castus) found in parts of Asia and Europe. It is claimed to treat infertility and to lessen symptoms that may occur before or during a woman’s menstrual period, such as headaches and irregular bleeding. Monk’s pepper may affect levels of reproductive hormones in the blood. It is a type of phytomedicine. Also called chaste tree berry and Vitex.

monoamine oxidase inhibitor    listen   (MAH-noh-uh-MEEN OK-sih-days 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. A monoamine oxidase inhibitor is a type of antidepressant. Also called MAO inhibitor.

monoclonal antibody    listen   (MAH-noh-KLOH-nul AN-tee-BAH-dee)
A type of protein made in the laboratory that can bind to substances in the body, including cancer cells. There are many kinds of monoclonal antibodies. A monoclonal antibody is made so that it binds to only one substance. Monoclonal antibodies are being used to treat some types of cancer. They can be used alone or to carry drugs, toxins, or radioactive substances directly to cancer cells.

monoclonal antibody Ch14.18    listen   (MAH-noh-KLOH-nul AN-tee-BAH-dee…)
A substance being studied in the treatment of cancer. It binds to a molecule called GD2, which is found in greater than normal amounts on some types of cancer cells. This helps cells of the immune system kill the cancer cells. It is a type of monoclonal antibody. Also called Ch14.18 and MOAB Ch14.18.

monoclonal antibody HuM195    listen   (MAH-noh-KLOH-nul AN-tee-BAH-dee …)
A substance being studied in the treatment of myelodysplastic syndromes and some types of leukemia. It binds to CD33, a protein on the surface of certain normal blood stem cells and some abnormal blood cells. It causes the immune system to kill these cells. Monoclonal antibody HuM195 is a type of monoclonal antibody. Also called lintuzumab and MoAb HuM195.

monoclonal B-cell lymphocytosis    listen   (MAH-noh-KLOH-nul B-sel LIM-foh-sy-TOH-sis)
A condition in which a higher-than-normal number of identical B cells are found in the blood. People with monoclonal B-cell lymphocytosis may develop other B-cell diseases, such as chronic lymphocytic leukemia (CLL). Also called MBL.

monoclonal gammopathy of undetermined significance    listen   (MAH-noh-KLOH-nul ga-MAH-puh-thee ... UN-deh-TER-mind sig-NIH-fih-kunts)
A benign condition in which there is a higher-than-normal level of a protein called M protein in the blood. Patients with monoclonal gammopathy of undetermined significance are at an increased risk of developing cancer. Also called MGUS.

monoclonal protein    listen   (MAH-noh-KLOH-nul 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. Also called M protein.

monocyte    listen   (MAH-noh-site)
A type of immune cell that is made in the bone marrow and travels through the blood to tissues in the body where it becomes a macrophage. Macrophages surround and kill microorganisms, ingest foreign material, remove dead cells, and boost immune responses. A monocyte is a type of white blood cell and a type of phagocyte.

monomer    listen   (MAH-noh-mer)
A molecule that can join with other identical monomers to form a larger structure called a polymer.

monotherapy    listen   (MAH-noh-THAYR-uh-pee)
Therapy that uses one type of treatment, such as radiation therapy or surgery alone, to treat a certain disease or condition. In drug therapy, monotherapy refers to the use of a single drug to treat a disease or condition.

Montanide ISA-51    listen   (MON-tuh-nide ...)
A mixture of oil and water that is combined with a specific antigen to boost the immune response to that antigen. It is being studied in immunotherapy and as a way to increase the immune response to cancer vaccines. It is a type of immune modulator. Also called IFA and incomplete Freund's adjuvant.

montelukast    listen   (mon-teh-LOO-kast)
The active ingredient in a drug used to treat symptoms of asthma, such as trouble breathing, tight chest, wheezing, coughing, and runny nose. Montelukast blocks the action of a substance that causes airways in the lungs to narrow and causes other symptoms of asthma. It is a type of leukotriene receptor antagonist and a type of antiasthmatic agent.

montelukast sodium    listen   (mon-teh-LOO-kast SOH-dee-um)
A drug used to treat symptoms of asthma, such as trouble breathing, tight chest, wheezing, coughing, and runny nose. Montelukast sodium blocks the action of a substance that causes airways in the lungs to narrow and causes other symptoms of asthma. It is a type of leukotriene receptor antagonist and a type of antiasthmatic agent. Also called Singulair.

MOPP    listen  
An abbreviation for a chemotherapy combination used alone or with radiation therapy to treat Hodgkin lymphoma. It includes the drugs mechlorethamine hydrochloride, vincristine sulfate (Oncovin), procarbazine hydrochloride, and prednisone. Also called MOPP regimen.

MOPP regimen    listen   (… REH-jih-men)
An abbreviation for a chemotherapy combination used alone or with radiation therapy to treat Hodgkin lymphoma. It includes the drugs mechlorethamine hydrochloride, vincristine sulfate (Oncovin), procarbazine hydrochloride, and prednisone. Also called MOPP.

MORAb-009      
A substance being studied in the treatment of mesothelioma. MORAb-009 binds to a protein called mesothelin, which is found on some cancer cells. MORAb-009 may help the immune system kill cancer cells. It is a type of monoclonal antibody. Also called amatuximab and anti-mesothelin monoclonal antibody MORAb-009.

moral    listen   (MOR-ul)
Having to do with beliefs about what is right and wrong in terms of how people behave. Also called ethical.

morbidity    listen   (mor-BIH-dih-tee)
Refers to having a disease or a symptom of disease, or to the amount of disease within a population. Morbidity also refers to medical problems caused by a treatment.

Morinda citrifolia    listen   (moh-RIN-duh sih-trih-FOH-lee-uh)
A tropical shrub. An extract from the fruit is being studied as a treatment for cancer, and extracts from the fruit, leaves, or roots have been used in some cultures to treat other diseases. Also called noni.

morphine sulfate    listen   (MOR-feen SUL-fayt)
A drug used to treat moderate to severe pain. It binds to opioid receptors in the central nervous system and some other tissues. Morphine sulfate is made from opium. It is a type of opiate and a type of analgesic agent.

morphology    listen   (mor-FAH-loh-jee)
The science of the form and structure of organisms (plants, animals, and other forms of life).

mortality    listen   (mor-TA-lih-tee)
Refers to the state of being mortal (destined to die). In medicine, a term also used for death rate, or the number of deaths in a certain group of people in a certain period of time. Mortality may be reported for people who have a certain disease, live in one area of the country, or who are of a certain gender, age, or ethnic group.

motexafin gadolinium    listen   (moh-TEK-suh-fin GA-doh-LIH-nee-um)
A substance being studied in the treatment and diagnosis of some types of cancer. It builds up in some cancer cells, which may make them easier to kill with radiation therapy and chemotherapy. Motexafin gadolinium is also used in magnetic resonance imaging (MRI) to help find cancer cells in the body. It is a type of radiosensitizing agent, a type of chemosensitizing agent, and a type of contrast agent. Also called gadolinium texaphyrin.

motexafin lutetium    listen   (moh-TEK-suh-fin loo-TEE-shee-um)
A substance that is being studied in the treatment of cancer using photodynamic therapy. It belongs to the family of drugs called metallotexaphyrins. Also called lutetium texaphyrin.

motor    listen   (MOH-ter)
In medicine, having to do with the movement of body parts.

motor neuron disease    listen   (MOH-ter NOOR-on dih-ZEEZ)
A type of disease in which the nerve cells in the brain that act on muscle cells break down and stop working. This affects basic activities such as speaking, walking, breathing, and swallowing. Symptoms include muscle weakness, wasting, twitching, trouble swallowing, and slowly becoming paralyzed. Motor neuron diseases are sometimes inherited. Amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease) is the most common type of motor neuron disease.

Motrin    listen   (MOH-trin)
A drug used to treat fever, swelling, pain, and redness by preventing the body from making a substance that causes inflammation. It is a type of nonsteroidal anti-inflammatory drug (NSAID). Also called Advil and ibuprofen.

mouse model    listen   (... MAH-dul)
The use of special strains of mice to study a human disease or condition, and how to prevent and treat it.

moxibustion    listen   (MOK-sih-BUS-chun)
In traditional Chinese medicine, a type of heat therapy in which an herb is burned on or above the skin to warm and stimulate an acupuncture point or affected area.

moxifloxacin    listen   (MOK-sih-FLOK-suh-sin)
A drug used to treat bacterial infections. It is a type of fluoroquinolone. Also called Avelox and moxifloxacin hydrochloride.

moxifloxacin hydrochloride    listen   (MOK-sih-FLOK-suh-sin HY-droh-KLOR-ide)
A drug used to treat bacterial infections. It is a type of fluoroquinolone. Also called Avelox and moxifloxacin.

Mozobil    listen   (MOH-zoh-bil)
A drug used before autologous stem cell transplantation in patients with non-Hodgkin lymphoma or multiple myeloma. Mozobil is given together with granulocyte-colony stimulating factor (G-CSF) to help move stem cells from the bone marrow to the blood. The stem cells can then be collected, stored, and given back to the patient. Mozobil is a type of chemokine receptor antagonist. Also called AMD 3100 and plerixafor.

MP470      
A substance being studied in the treatment of some types of cancer. It may block certain proteins involved in cancer cell growth and DNA repair. Blocking these proteins may make cancer cells more sensitive to anticancer drugs and radiation therapy. MP470 is a type of tyrosine kinase inhibitor. Also called amuvatinib.

MPNST      
A type of soft tissue sarcoma that develops in cells that form a protective sheath (covering) around peripheral nerves, which are nerves that are outside of the central nervous system (brain and spinal cord). Also called malignant peripheral nerve sheath tumor.

MR      
A measure of how fast cancer cells are dividing and growing. To find the MR, the number of cells dividing in a certain amount of cancer tissue is counted. MR is used to help find the stage of melanoma (a type of skin cancer) and other types of cancer. Higher MRs are linked with lower survival rates. Also called mitotic rate.

MRA      
A procedure that uses radio waves and a powerful magnet linked to a computer to create detailed pictures of the blood vessels and blood flow inside the body. A dye may be injected into a vein to make the blood vessels and blood flow easier to see. MRA may be used to check for aneurysms (a bulge in the blood vessel wall), blockages in the arteries, blood clots, and other blood vessel problems. Also called magnetic resonance angiography.

MRI      
A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called magnetic resonance imaging, NMRI, and nuclear magnetic resonance imaging.

mRNA      
A type of RNA found in cells. mRNA molecules carry the genetic information needed to make proteins. They carry the information from the DNA in the nucleus of the cell to the cytoplasm where the proteins are made. Also called messenger RNA.

MRSI      
A noninvasive imaging method that provides information about cellular activity (metabolic information). It is used along with magnetic resonance imaging (MRI) which provides information about the shape and size of the tumor (spatial information). Also called 1H-nuclear magnetic resonance spectroscopic imaging, magnetic resonance spectroscopic imaging, and proton magnetic resonance spectroscopic imaging.

MS 209      
A substance that is being studied for its ability to make cancer cells respond better to chemotherapy drugs to which they have become resistant. It is a type of quinolone antibiotic.

MS-275      
A substance that is being studied in the treatment of cancers of the blood. It belongs to the family of drugs called histone deacetylase inhibitors.

MSI      
A change that occurs in the DNA of certain cells (such as tumor cells) in which the number of repeats of microsatellites (short, repeated sequences of DNA) is different than the number of repeats that was in the DNA when it was inherited. The cause of MSI may be a defect in the ability to repair mistakes made when DNA is copied in the cell. Also called microsatellite instability.

MTD      
The highest dose of a drug or treatment that does not cause unacceptable side effects. The MTD is determined in clinical trials by testing increasing doses on different groups of people until the highest dose with acceptable side effects is found. Also called maximum tolerated dose.

mTOR      
A protein that helps control several cell functions, including cell division and survival, and binds to rapamycin and other drugs. mTOR may be more active in some types of cancer cells than it is in normal cells. Blocking mTOR may cause the cancer cells to die. It is a type of serine/threonine protein kinase. Also called mammalian target of rapamycin.

mTOR inhibitor    listen   (… in-HIH-bih-ter)
A substance that blocks a protein called mTOR, which helps control cell division. Blocking mTOR’s action may keep cancer cells from growing and prevent the growth of new blood vessels that tumors need to grow. Some mTOR inhibitors are used to treat cancer.

MTX      
A drug used to treat some types of cancer, rheumatoid arthritis, and severe skin conditions, such as psoriasis. MTX stops cells from making DNA and may kill cancer cells. It is a type of antimetabolite. Also called amethopterin, methotrexate, and Rheumatrex.

MUC-1      
A protein found on certain epithelial cells, which line the inside and outside surfaces of the body. It may be found in higher than normal amounts in patients with some types of cancer, including breast, ovarian, lung, and prostate cancers, or in other conditions. Measuring the amount of MUC-1 in the blood may help to find out how well cancer treatment is working or if cancer has come back. MUC-1 is a type of tumor marker.

mucin/peptide    listen   (MYOO-sin/PEP-tide)
A protein/sugar compound made by some cancer cells.

mucinous    listen   (MYOO-sin-us)
Containing or resembling mucin, the main compound in mucus.

mucinous carcinoma    listen   (MYOO-sin-us KAR-sih-NOH-muh)
A type of cancer that begins in cells that line certain internal organs and produce mucin (the main component of mucus).

mucosa    listen   (myoo-KOH-suh)
The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucosa make mucus (a thick, slippery fluid). Also called mucous membrane.

mucosa-associated lymphoid tissue lymphoma    listen   (myoo-KOH-suh-uh-SOH-see-ay-ted LIM-foyd TIH-shoo lim-FOH-muh)
A type of cancer that arises in cells in mucosal tissue that are involved in antibody production. Also called MALT lymphoma.

mucositis    listen   (myoo-koh-SY-tis)
A complication of some cancer therapies in which the lining of the digestive system becomes inflamed. Often seen as sores in the mouth.

mucous membrane    listen   (MYOO-kus MEM-brayn)
The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucous membrane make mucus (a thick, slippery fluid). Also called mucosa.

mucus    listen   (MYOO-kus)
A thick, slippery fluid made by the membranes that line certain organs of the body, including the nose, mouth, throat, and vagina.

mucus colitis    listen   (MYOO-kus koh-LY-tis)
A disorder of the intestines commonly marked by abdominal pain, bloating, and changes in a person’s bowel habits. This may include diarrhea or constipation, or both, with one occurring after the other. Also called IBS, irritable bowel syndrome, irritable colon, and spastic colon.

muJ591      
A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

Mullerian tumor    listen   (myoo-LAYR-ee-un TOO-mer)
A rare cancer of the uterus, ovary, or fallopian tubes.

multicenter study    listen   (MUL-tee-SEN-ter STUH-dee)
A clinical trial that is carried out at more than one medical institution.

multicentric breast cancer    listen   (MUL-tee-SEN-trik brest KAN-ser)
Breast cancer in which there is more than one tumor, all of which have formed separately from one another. The tumors are likely to be in different quadrants (sections) of the breast. Multicentric breast cancers are rare.

multidisciplinary    listen   (MUL-tee-DIH-sih-plih-NAYR-ee)
In medicine, a term used to describe a treatment planning approach or team that includes a number of doctors and other health care professionals who are experts in different specialties (disciplines). In cancer treatment, the primary disciplines are medical oncology (treatment with drugs), surgical oncology (treatment with surgery), and radiation oncology (treatment with radiation).

multidisciplinary opinion    listen   (MUL-tee-DIH-sih-plih-NAYR-ee uh-PIN-yun)
A treatment planning approach in which a number of doctors who are experts in different specialties (disciplines) review and discuss the medical condition and treatment options of a patient. In cancer treatment, a multidisciplinary opinion may include that of a medical oncologist (who provides cancer treatment with drugs), a surgical oncologist (who provides cancer treatment with surgery), and a radiation oncologist (who provides cancer treatment with radiation). Also called tumor board review.

multidrug resistance    listen   (MUL-tee-... reh-ZIH-stunts)
Adaptation of tumor cells to anticancer drugs in ways that make the drugs less effective.

multidrug resistance inhibition    listen   (MUL-tee-... reh-ZIH-stunts in-HIH-bih-shun)
Treatment used to make cancer cells less resistant to anticancer drugs.

multifocal breast cancer    listen   (mul-tee-FOH-kul brest KAN-ser)
Breast cancer in which there is more than one tumor, all of which have arisen from one original tumor. The tumors are likely to be in the same quadrant (section) of the breast.

MultiHance    listen   (MUL-tee-HANTS)
A drug used in MRI to help make clear pictures of blood vessels in the brain, spine, and nearby tissues. It is also being studied as a way to find abnormal areas in the liver and other organs and to help diagnose cancer. MultiHance is a type of contrast agent. Also called gadobenate dimeglumine.

multimodality therapy    listen   (MUL-tee-moh-DA-lih-tee THAYR-uh-pee)
Therapy that combines more than one method of treatment. Also called combination therapy and multimodality treatment.

multimodality treatment    listen   (MUL-tee-moh-DA-lih-tee TREET-ment)
Therapy that combines more than one method of treatment. Also called combination therapy and multimodality therapy.

multiple endocrine adenomatosis    listen   (MUL-tih-pul EN-doh-krin A-deh-NOH-muh-TOH-sis)
A rare, inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid and pituitary glands and the pancreas. These tumors are usually benign (not cancer). They cause the glands to secrete high levels of hormones, which can lead to other medical problems, such as kidney stones, fertility problems, and severe ulcers. In some cases, tumors inside the pancreas can become malignant (cancer). Also called MEN1 syndrome, multiple endocrine neoplasia type 1 syndrome, and Wermer syndrome.

multiple endocrine adenomatosis type 2    listen   (MUL-tih-pul EN-doh-krin A-deh-NOH-muh-TOH-sis ...)
A rare, genetic disorder that affects the endocrine glands and can cause tumors in the thyroid gland, parathyroid glands, and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. Multiple endocrine adenomatosis type 2 is caused by a mutation (change) in a gene called RET, and is divided into three subtypes (MEN2A, MEN2B, and FMTC). People with all subtypes of multiple endocrine adenomatosis type 2 have an increased risk of medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. Also called MEN2, MEN2 syndrome, and multiple endocrine neoplasia type 2 syndrome.

multiple endocrine adenomatosis type 2B    listen   (MUL-tih-pul EN-doh-krin A-deh-NOH-muh-TOH-sis ...)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the adrenal glands and growths around the nerves in the lips, tongue, lining of the mouth, and eyelids. Gastrointestinal symptoms and trouble with the spine or bones in the feet and thighs may also occur. Multiple endocrine adenomatosis type 2B is caused by a mutation (change) in a gene called RET. Also called MEN2B, MEN2B syndrome, and multiple endocrine neoplasia type 2B syndrome.

multiple endocrine adenomatosis type 2A    listen   (MUL-tih-pul EN-doh-krin A-deh-NOH-muh-TOH-sis ...)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the parathyroid glands and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. An itchy skin condition may also occur. Multiple endocrine adenomatosis type 2A is caused by a mutation (change) in a gene called RET. Also called MEN2A, MEN2A syndrome, multiple endocrine neoplasia type 2A syndrome, and Sipple syndrome.

multiple endocrine neoplasia syndrome    listen   (MUL-tih-pul EN-doh-krin NEE-oh-PLAY-zhuh SIN-drome)
An inherited condition that may result in the development of cancers of the endocrine system. There are several types of multiple endocrine neoplasia syndrome, and patients with each type may develop different types of cancer. The altered genes that cause each type can be detected with a blood test. Also called MEN syndrome.

multiple endocrine neoplasia type 1 syndrome    listen   (MUL-tih-pul EN-doh-krin NEE-oh-PLAY-zhuh ... SIN-drome)
A rare, inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid and pituitary glands and the pancreas. These tumors are usually benign (not cancer). They cause the glands to secrete high levels of hormones, which can lead to other medical problems, such as kidney stones, fertility problems, and severe ulcers. In some cases, tumors inside the pancreas can become malignant (cancer). Also called MEN1 syndrome, multiple endocrine adenomatosis, and Wermer syndrome.

multiple endocrine neoplasia type 2B syndrome    listen   (MUL-tih-pul EN-doh-krin NEE-oh-PLAY-zhuh ... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the adrenal glands and growths around the nerves in the lips, tongue, lining of the mouth, and eyelids. Gastrointestinal symptoms and trouble with the spine or bones in the feet and thighs may also occur. Multiple endocrine neoplasia type 2B syndrome is caused by a mutation (change) in a gene called RET. Also called MEN2B, MEN2B syndrome, and multiple endocrine adenomatosis type 2B.

multiple endocrine neoplasia type 2A syndrome    listen   (MUL-tih-pul EN-doh-krin NEE-oh-PLAY-zhuh ... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and causes a type of thyroid cancer called medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. It may also cause benign (noncancerous) tumors in the parathyroid glands and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. An itchy skin condition may also occur. Multiple endocrine neoplasia type 2A syndrome is caused by a mutation (change) in a gene called RET. Also called MEN2A, MEN2A syndrome, multiple endocrine adenomatosis type 2A, and Sipple syndrome.

multiple endocrine neoplasia type 2 syndrome    listen   (MUL-tih-pul EN-doh-krin NEE-oh-PLAY-zhuh ... SIN-drome)
A rare, genetic disorder that affects the endocrine glands and can cause tumors in the thyroid gland, parathyroid glands, and adrenal glands. The affected endocrine glands may make high levels of hormones, which can lead to other medical problems such as high blood pressure and kidney stones. Multiple endocrine neoplasia type 2 syndrome is caused by a mutation (change) in a gene called RET, and is divided into three subtypes (MEN2A, MEN2B, and FMTC). People with all subtypes of multiple endocrine neoplasia type 2 syndrome have an increased risk of medullary thyroid cancer, pheochromocytoma, and parathyroid gland cancer. Also called MEN2, MEN2 syndrome, and multiple endocrine adenomatosis type 2.

multiple hamartoma syndrome    listen   (MUL-tih-pul HA-mar-TOH-muh SIN-drome)
An inherited disorder marked by the formation of many noncancerous growths called hamartomas. These growths occur in the skin, breast, thyroid, colon, intestines, and inside of the mouth. Patients with multiple hamartoma syndrome are at increased risk of certain types of cancer, including breast and thyroid. Also called Cowden disease and Cowden syndrome.

multiple myeloma    listen   (MUL-tih-pul MY-eh-LOH-muh)
A type of cancer that begins in plasma cells (white blood cells that produce antibodies). Also called Kahler disease, myelomatosis, and plasma cell myeloma.

multiple sclerosis    listen   (MUL-tih-pul skleh-ROH-sis)
A disorder of the central nervous system marked by weakness, numbness, a loss of muscle coordination, and problems with vision, speech, and bladder control. Multiple sclerosis is thought to be an autoimmune disease in which the body's immune system destroys myelin. Myelin is a substance that contains both protein and fat (lipid), serving as a nerve insulator and helping in the transmission of nerve signals.

multiplicity    listen   (MUL-tih-PLIH-sih-tee)
A large number or variety.

multitargeted receptor tyrosine kinase inhibitor ABT-869    listen   (MUL-tee-TAR-geh-ted reh-SEP-ter TY-ruh-seen KY-nays in-HIH-bih-ter …)
A substance being studied in the treatment of several types of cancer. Multitargeted receptor tyrosine kinase inhibitor ABT-869 blocks the action of several growth factors. It may also block the growth of new blood vessels that tumors need to grow and may cause cancer cells to die. It is a type of receptor tyrosine kinase inhibitor and a type of angiogensis inhibitor. Also called ABT-869.

mung bean    listen   (mung been)
A type of bean grown in warm climates, usually for its seed and for bean sprouts. Mung bean may have anticancer effects.

muramyl tripeptide phosphatidylethanolamine    listen   (MYOOR-uh-mil try-PEP-tide FOS-fuh-TY-dul-EH-thuh-NOH-luh-meen)
A drug being studied in the treatment of young adults with bone cancer that has gotten worse or come back. Muramyl tripeptide phosphatidylethanolamine activates certain types of white blood cells and helps the immune system kill cancer cells. It is a type of immunostimulant. Also called L-MTP-PE, MEPACT, and mifamurtide.

muromonab-CD3    listen   (MYOO-roh-MOH-nab …)
A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

muscle wasting    listen   (MUH-sul WAY-sting)
A weakening, shrinking, and loss of muscle caused by disease or lack of use. Muscle wasting decreases strength and the ability to move.

musculoskeletal    listen   (MUS-kyoo-loh-SKEH-leh-tul)
Having to do with muscles, bones, tendons, ligaments, joints, and cartilage.

MUSE    listen  
A method used to treat impotence (inability to have an erection). A suppository, in the form of a very small pellet, is inserted through the tip of the penis into the urethra. The suppository contains the drug alprostadil, which increases the flow of blood to the penis and causes an erection. Also called medicated urethral system for erection.

music therapy    listen   (MYOO-sik THAYR-uh-pee)
Treatment that uses music to help relieve pain or stress and promote well-being. It is being studied in the treatment of several cancer-related problems and other conditions.

Mustargen    listen   (MUS-ter-jen)
A drug used to treat non-Hodgkin lymphoma, advanced Hodgkin lymphoma, chronic leukemia, mycosis fungoides, and a type of lung cancer called bronchogenic carcinoma. It is also being studied in the treatment of other types of cancer. Mustargen damages the cell's DNA and may kill cancer cells. It is a type of alkylating agent. Also called mechlorethamine hydrochloride and mustine.

mustine    listen   (MUS-teen)
A drug used to treat non-Hodgkin lymphoma, advanced Hodgkin lymphoma, chronic leukemia, mycosis fungoides, and a type of lung cancer called bronchogenic carcinoma. It is also being studied in the treatment of other types of cancer. Mustine damages the cell's DNA and may kill cancer cells. It is a type of alkylating agent. Also called mechlorethamine hydrochloride and Mustargen.

mutagen    listen   (MYOO-tuh-jen)
Anything that causes a mutation (a change in the DNA of a cell). DNA changes caused by mutagens may harm cells and cause certain diseases, such as cancer. Examples of mutagens include radioactive substances, x-rays, ultraviolet radiation, and certain chemicals.

Mutamycin    listen   (MYOO-tuh-MY-sin)
A drug used to treat advanced cancer of the stomach and pancreas that has not gotten better with other treatment. It is also being studied in the treatment of other types of cancer. Mutamycin comes from bacteria. It damages the cell’s DNA and may kill cancer cells. It is a type of anticancer antibiotic. Also called mitomycin C and Mitozytrex.

mutate    listen   (MYOO-tayt)
To change the genetic material of a cell. The changes (mutations) can be harmful, beneficial, or have no effect.

mutation    listen   (myoo-TAY-shun)
Any change in the DNA sequence of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment. Mutations can be harmful, beneficial, or have no effect. If they occur in cells that make eggs or sperm, they can be inherited; if mutations occur in other types of cells, they are not inherited. Certain mutations may lead to cancer or other diseases.

mutation carrier    listen   (myoo-TAY-shun KAYR-ee-er)
A person who has a mutated (changed) copy of a gene. This change may cause a disease in that person or in his or her children.

myalgia    listen   (my-AL-juh)
Pain in a muscle or group of muscles.

myasthenia gravis    listen   (MY-us-THEE-nee-uh GRA-vis)
A disease in which antibodies made by a person’s immune system prevent certain nerve-muscle interactions. It causes weakness in the arms and legs, vision problems, and drooping eyelids or head. It may also cause paralysis and problems with swallowing, talking, climbing stairs, lifting things, and getting up from a sitting position. The muscle weakness gets worse during activity, and improves after periods of rest.

Mycobutin    listen   (MY-koh-BYOO-tin)
A drug used to prevent the spread of a bacterium called in patients with advanced HIV (the virus that causes AIDS) infection. It blocks an enzyme that the bacteria need to grow. It is a type of antibiotic. Also called rifabutin.

mycophenolate mofetil    listen   (my-koh-FEH-noh-layt MOH-feh-til)
A drug used to prevent graft-versus-host disease (GVHD) after organ transplants. It is also being studied in the prevention of GVHD after stem cell transplants for cancer, and in the treatment of some autoimmune disorders. Mycophenolate mofetil is a type of immunosuppressive agent. Also called CellCept.

mycosis fungoides    listen   (my-KOH-sis fun-GOY-deez)
A type of non-Hodgkin lymphoma that first appears on the skin and can spread to the lymph nodes or other organs such as the spleen, liver, or lungs.

mycosis fungoides patch    listen   (my-KOH-sis fun-GOY-deez …)
A flat, red area on the skin of patients who have mycosis fungoides. The patches may look like a thin, red rash and may be itchy. They are most common on the chest, groin, hips, buttocks, and under the arms. They may look like eczema or psoriasis.

mycosis fungoides plaque    listen   (my-KOH-sis fun-GOY-deez plak)
In mycosis fungoides, an area of skin that is thickened, raised, red, scaly, and itchy.

Mycostatin    listen   (MY-koh-STA-tin)
A drug used to treat infections caused by fungi (a type of microorganism). It is made by certain strains of bacteria and kills fungi by binding to their membranes. Mycostatin is a type of antifungal agent.

myelin    listen   (MY-eh-lin)
The fatty substance that covers and protects nerves.

myeloablation    listen   (MY-eh-loh-a-BLAY-shun)
A severe form of myelosuppression. Myelosuppression is a condition in which bone marrow activity is decreased, resulting in fewer red blood cells, white blood cells, and platelets. It is a side effect of some cancer treatments. Also called severe myelosuppression.

myeloablative chemotherapy    listen   (MY-eh-loh-a-BLAY-tiv KEE-moh-THAYR-uh-pee)
High-dose chemotherapy that kills cells in the bone marrow, including cancer cells. It lowers the number of normal blood-forming cells in the bone marrow, and can cause severe side effects. Myeloablative chemotherapy is usually followed by a bone marrow or stem cell transplant to rebuild the bone marrow.

myeloblast    listen   (MY-eh-loh-blast)
A type of immature white blood cell that forms in the bone marrow. Myeloblasts become mature white blood cells called granulocytes (neutrophils, basophils, and eosinophils).

myeloblastic    listen   (MY-eh-loh-BLAS-tik)
Refers to myeloblasts (a type of immature cell that forms in the bone marrow).

myelodysplasia    listen   (MY-eh-loh-dis-PLAY-zhuh)
Abnormal bone marrow cells that may lead to myelogenous leukemia.

myelodysplastic syndrome    listen   (MY-eh-loh-dis-PLAS-tik SIN-drome)
A type of cancer in which the bone marrow does not make enough healthy blood cells (white blood cells, red blood cells, and platelets) and there are abnormal cells in the blood and/or bone marrow. When there are fewer healthy blood cells, infection, anemia, or bleeding may occur. Sometimes, myelodysplastic syndrome becomes acute myeloid leukemia (AML). Also called MDS.

myelofibrosis    listen   (MY-eh-loh-fy-BROH-sis)
A disorder in which the bone marrow is replaced by fibrous tissue.

myelogenous    listen   (MY-eh-LAH-jeh-nus)
Having to do with, produced by, or resembling the bone marrow. Sometimes used as a synonym for myeloid; for example, acute myeloid leukemia and acute myelogenous leukemia are the same disease.

myelogram    listen   (MY-eh-loh-gram)
An x-ray of the spinal cord after an injection of dye into the space between the lining of the spinal cord and brain.

myeloid    listen   (MY-eh-loyd)
Having to do with or resembling the bone marrow. May also refer to certain types of hematopoietic (blood-forming) cells found in the bone marrow. Sometimes used as a synonym for myelogenous; for example, acute myeloid leukemia and acute myelogenous leukemia are the same disease.

myeloma    listen   (MY-eh-LOH-muh)
Cancer that arises in plasma cells, a type of white blood cell.

myelomatosis    listen   (MY-eh-loh-muh-TOH-sis)
A type of cancer that begins in plasma cells (white blood cells that produce antibodies). Also called Kahler disease, multiple myeloma, and plasma cell myeloma.

myelomonocyte    listen   (MY-eh-loh-MAH-noh-site)
An abnormal type of white blood cell that is found in chronic myelomonocytic leukemia. These cells are similar to both monocytes and myelocytes (immature cells that develop into different types of immune system cells).

myeloproliferative neoplasm    listen   (MY-eh-loh-proh-LIH-feh-ruh-tiv NEE-oh-PLA-zum)
A type of disease in which the bone marrow makes too many red blood cells, platelets, or certain white blood cells. Myeloproliferative neoplasms usually get worse over time as the number of extra cells build up in the blood and/or bone marrow. This may cause bleeding problems, anemia, infection, fatigue, or other signs and symptoms. Certain myeloproliferative neoplasms may become acute myeloid leukemia (AML). Myeloproliferative neoplasms include chronic myelogenous leukemia (CML), polycythemia vera, primary myelofibrosis, essential thrombocythemia, chronic neutrophilic leukemia, and chronic eosinophilic leukemia. Also called chronic myeloproliferative neoplasm.

myelosclerosis with myeloid metaplasia    listen   (MY-eh-loh-skleh-ROH-sis ... MY-eh-loyd meh-tuh-PLAY-zhuh)
A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made in organs such as the liver and the spleen, instead of in the bone marrow. This disease is marked by an enlarged spleen and progressive anemia. Also called agnogenic myeloid metaplasia, chronic idiopathic myelofibrosis, idiopathic myelofibrosis, and primary myelofibrosis.

myelosuppression    listen   (MY-eh-loh-suh-PREH-shun)
A condition in which bone marrow activity is decreased, resulting in fewer red blood cells, white blood cells, and platelets. Myelosuppression is a side effect of some cancer treatments. When myelosuppression is severe, it is called myeloablation.

myelosuppressive therapy    listen   (MY-eh-loh-suh-PREH-siv THAYR-uh-pee)
Treatment that inhibits blood cell production.

Myleran    listen   (MY-leh-ran)
A drug used to treat chronic myelogenous leukemia (CML). It is also used with other drugs to prepare patients with CML for a stem cell transplant. It is also being studied in the treatment of other types of cancer. Myleran attaches to DNA in cells and may kill cancer cells. It is a type of alkylating agent. Also called busulfan and Busulfex.

Mylosar    listen   (MY-loh-sar)
A drug that is used to treat myelodysplastic syndromes and is being studied in the treatment of other types of cancer. It belongs to the family of drugs called antimetabolites. Also called azacitidine and Vidaza.

Mylotarg    listen   (MY-loh-targ)
A drug that was used to treat acute myeloid leukemia (AML) that recurred (came back). It was used in older patients who were not able to take other anticancer drugs. Mylotarg was taken off the market but continues to be studied in clinical trials for the treatment of certain types of leukemia. It contains a monoclonal antibody that binds to a protein called CD33, which is found on some leukemia cells. It also contains a toxic substance, which may help kill cancer cells. Mylotarg is a type of antibody-drug conjugate. Also called gemtuzumab ozogamicin.

myoclonic jerk    listen   (MY-oh-KLAH-nik …)
A sudden, brief, strong contraction of a muscle or group of muscles that cannot be controlled.

myoinositol    listen   (my-oh-ih-NOH-sih-TOL)
A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Myoinositol helps cells make membranes and respond to messages from their environment. It has the same chemical formula as glucose (the chief source of energy for living organisms) but has a different arrangement of atoms. It is found in beans, peas, brown rice, wheat bran and nuts. It is water-soluble (can dissolve in water) and must be taken in every day. Myoinositol is being studied in the prevention of cancer. Also called inositol.

myometrium    listen   (my-oh-MEE-tree-um)
The muscular outer layer of the uterus.

myristyl nicotinate cream    listen   (mih-RIS-til NIH-kuh-TIH-nayt kreem)
A substance being studied in the prevention of skin cancer. Myristyl nicotinate cream is also being studied as a way to help lessen the side effects of retinoic acid (a form of vitamin A) when it is used to treat skin that has been damaged by the sun. Myristyl nicotinate cream contains a form of niacin (a member of the vitamin B complex). It is a type of chemopreventive agent.

MZL      
An indolent (slow-growing) type of B-cell non-Hodgkin lymphoma that begins forming in certain areas (the marginal zones) of lymph tissue. There are three types based on whether it forms in the spleen, lymph nodes, or other lymphoid tissue that contains a lot of B cells (a type of white blood cell). Also called marginal zone B-cell lymphoma and marginal zone lymphoma.

Ménétrier disease    listen   (MAY-nay-tree-AY dih-ZEEZ)
A condition marked by inflammation and ulcers (breaks on the skin or on the surface of an organ) of the mucosa (inner lining) of the stomach and by overgrowth of the cells that make up the mucosa. Symptoms include vomiting, diarrhea, and weight loss. Patients with Ménétrier disease may be at a higher risk of stomach cancer. Also called gastric mucosal hypertrophy and giant hypertrophic gastritis.

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