· MA Master of Arts degree.
· MAB or MoAB. Monoclonal antibodies.
· macrophages [mak´ roe faj] Large and versatile immune cells that dispose of foreign substances in our body. Garbage pick-up cells.
· maintenance therapy Treatment used to prevent a recurrence in patients who are in remission.
· malignant [mah lig´ nant] Cancerous or life-threatening, tending to become progressively worse. Cancer can invade and destroy nearby tissue and spread to other parts of the body.
· malignant melanoma [mel ih no´ ma] A form of skin cancer that arises in melanocytes, the cells that produce skin pigment. It often begins as a dark, irregularly shaped mole. This form of cancer can spread to the brain.
· malignant meningioma A very rare form of meningioma, it includes the anaplastic meningioma and papillary meningioma. The atypical meningioma is not clearly malignant, but can invade and spread within the brain.
· malignant peripheral nerve sheath tumor The rare, malignant form of an acoustic neuroma. Abbreviated MPNST.
· Mannitol [man´ ih tol] A medication used to reduce brain swelling and elevated intracranial pressure. Also used to temporarily disrupt the blood brain barrier prior to some
forms of chemotherapy.
· mass effect Swelling or enlargement of the brain due to the bulk of a tumor, the blockage of fluid, and/or excess accumulation of fluid within the skull.
· MBA Master of Business Administration degree.
· MD Medical Doctor degree.
· MDiv Master of Divinity degree.
· MDL Medulloblastoma.
· measurable disease A tumor that can be accurately measured in size. This information can be used to judge growth rate or response to treatment.
· median survival Median means the middle value. An equal number of people live longer as die earlier than the median survival number.
· medical device An instrument, machine, implant or similar article that is intended for use in the diagnosis, treatment, or prevention of disease. It can be anything from a thermometer to an artificial heart to an at-home pregnancy test.
· medical oncologist Cancer specialist. A physician trained in diagnosing and treating cancer.
· Medicaid A joint federal and state program that helps with medical costs for some people with low incomes and limited resources. Medicaid programs vary from state of state.
· Medicare The federal health insurance program for people 65 years of age or older, certain younger people with disabilities, and people with End-Stage Renal Disease. It is the largest health insurance program in the US, covering about 41 million Americans. It is administered by the Centers for Medicare & Medicaid Services (CMS) of the Department of Health and Human Services of the US government. Medicare Part A is hospital insurance, covering inpatient hospital stays, care in a skilled nursing facility, home healthcare, and hospital care. Part B is medical insurance. It helps pay for doctors’ services, outpatient hospital care, and other medical services not covered by Part A.
· MEDLINE Provides searches for published medical literature from an extensive database. The online version is PubMed.
· medulla [meh dull´ ah] The center or inner region. In the CNS, refers to the spinal cord and its continuation in the skull — the medulla oblongata.
· medulla oblongata [meh dull´ ah • ob long ah´ ta] Part of the brain stem, it connects the brain with the spinal cord.
· medulloblastoma [med´ you low blas toe´ ma] This tumor represents 15-20% of pediatric brain tumors. Thirty percent of these tumors occur in adults. It commonly occurs in the
cerebellum, is fast growing, and can spread to other parts of the central nervous system. It is sometimes called a primitive neuroectodermal tumor (PNET). Commonly abbreviated MDL.
· MEG Magnetoencephalogram. A scan that measures the magnetic fields created by nerve cells.
· melanoma [mel ih no´ ma] A form of skin cancer that arises in melanocytes, the cells that produce skin pigment. It often begins as a dark, irregularly shaped mole. This form of cancer can spread to the brain.
· melatonin [mel ah toe´ nin] A hormone produced by the pineal gland and thought to control biological rhythms. May also be a radiosensitizer for brain tumors and is currently
being tested for that purpose.
· membrane [mem´ brain] A thin layer of tissue covering a surface, lining a body cavity, or dividing a space or organ. The meninges consists of three membranes.
· meningeal [meh nin jee´ al] Refers to the meninges.
· meninges [meh nin´ jeez] Three, thin membranes that cover the brain and spinal cord. The outermost layer is the thick dura mater, the arachnoid is in the middle and the thin pia mater lies directly over the brain, following all its curves and indentations.
· meningioma [meh nin jee o´ ma] This usually benign tumor arises from the arachnoid cells of the meninges of the brain and spinal cord, represents about 20% of all primary brain tumors and occurs most commonly in middle-aged women.
· mental changes A common symptom of brain tumors. Includes alterations in memory, speech, communication and concentration. Also, intellectual problems, confusion and changes in behavior, temperament and personality.
· meta-analysis [MEHTA-uh-nal-ysis] A statistical method for combining and analyzing the results of several independently published studies in search of conclusions that may not have been immediately apparent when looking at the results of the smaller, single studies.
· metabolism [meh tab´ o lizm] The chemical and physical processes that occur to maintain the body and produce energy.
· metastasize [meh tas´ tah siz] To spread to another part of the body, usually through blood vessels, lymph channels, or spinal fluid.
· metastatic brain tumor [meh tah stat´ ick] A secondary brain tumor formed by cancer cells that began elsewhere in the body and traveled to the brain. Cancers that commonly spread to the brain include: lung cancer; breast cancer; colon cancer; melanoma; kidney cancer. A metastatic brain tumor can appear anywhere in the brain or spine. Multiple tumors can occur.
· methylated [METH-il-ated] (adjective). Methylation is the process of adding -CH3 (methyl) groups to specific DNA protein, which silences those genes and may contribute to tumor cell growth.
· MGMT Abbreviation for O6-methylguanine-DNA methyltransferase, a gene thatplays a role in DNA repair.
· microenvironment [MI-kro EN-vi´ron-ment] A small, specialized, isolated environment at the microscopic or cellular level, for example, the area immediately surrounding a tumor. The microenvironment plays a critical role in tumor initiation and progression, and may be an important factor in developing treatment approaches.
· microglia Tiny “scavenger” glial cells that play a role in the immune functions of the brain.
· microspheres Controlled-release drugs in a capsule. They are designed to dissolve slowly and release their contents over a pre-determined amount of time.
· microsurgery The use of a high-powered microscope during surgery. Microsurgery is widely used for brain tumor surgery.
· midbrain The part of the brain stem between the pons and the cerebral hemispheres.
· mitosis [my toe´ sis] Cell division.
· mitotic index/activity [my tot´ ik] An indication of how fast a tumor is growing. The proportion of cells in a sample that are undergoing mitosis.
· mitotic inhibitor [my tot´ ik] Drugs that kill cancer cells by interfering with cell division (mitosis).
· mixed glioma [glee o´ ma] These tumors contain a high proportion of more than one type of cell. Mixed gliomas commonly contain both astrocytes and oligodendrocytes. Occasionally, ependymal cells are also found. They are commonly grade II or III tumors. Also called oligoastrocytoma.
· MMPI Minnesota Multiphasic Personality Inventory test.
· MMSE Mini Mental Status Exam. Used to assess cognitive neuropsychological changes due to disease or its treatment.
· MoAB or MAB Monoclonal Antibodies.
· modality [moe dal´ ih tee] A method. Chemotherapy and surgery are two different treatment modalities.
· molecular marker [muh-LEH-kyoo-ler] 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 or signature molecule.
· molecule [moll ek´ yule] The smallest amount of a specific chemical substance that can exist alone. If it is broken down into its component parts, it is no longer recognizable. For
example, if water (H2O) is broken down it becomes one atom of oxygen and two atoms of hydrogen.
· monoclonal antibodies [mon o klon´ al • an´ te bod eze] Mass produced in the laboratory, they are substances (antibodies) that can locate and bind to a specific antigen (a unique property on the surface of a cell) wherever it is in the body. They are biological response modifiers with “homing device” properties. Chemicals or radiation tagged to the monoclonals might be delivered directly to tumor cells. Or, monoclonal antibodies themselves may be capable of tumor cell destruction. Often abbreviated MoAB or MAB.
· monocytes [mon´ o sitez] Large white blood cells that travel into tissues and develop, when needed, into macrophages, as part of the immune response. Monocytes and macrophages play a key role in phagocytosis, a process by which some cells “eat” other cells and foreign invaders. Monocytes produce monokines, a cytokine.
· monokine [mon´ o kyne] Powerful chemical substances secreted by monocytes and macrophages. These molecules help direct and regulate the immune response. Monokines
are one type of cytokine.
· morbidity [more bid´ ih tee] The presence of a disease, or complications resulting from treatment.
· mortality rate [more tal´ ih tee] The number of people who die within a specified period of time, such as a year, five years, 6 months etc.
· motor Movement, control of muscles. The “motor cortex” is located in the precentral gyrus of the frontal lobe.
· mouse model A breed of mouse genetically engineered to approximate the human tumor environment.
· MPH Master of Public Health degree.
· MRI angiography [an gee og´ rah fee] A diagnostic procedure done in the x-ray department to help visualize blood vessels. The person receives an injection of dye to outline the vessels on the x-ray or scan. Also called angiogram, arteriogram.
· MRI scan Magnetic Resonance Imaging. MRI is a scanning device that uses a magnetic field, radio waves, and a computer. Signals emitted by normal and diseased tissue during the scan are assembled into an image.
· MRS Magnetic Resonance Spectroscopy. An imaging device that depicts tissue function rather than shape.
· MS Master of Science degree.
· MSN Master of Science in Nursing degree.
· MST Median Survival Time.
· MSW Master of Social Work degree.
· MTD Maximum Tolerated Dose, a term used in Phase I studies where the goal is to achieve a balance between dosage and side effects.
· mucositis [mew ko sigh´ tiss] Inflammation of a mucous membrane. Mucositis in the mouth is called stomatitis; in the esophagus, it is called esophagitis.
· multi-disciplinary treatment team Health care provided by a range of specialists.
· multidrug resistance Adaptation of tumor cells to anticancer drugs in ways that make the drugs less effective.
· multimodality treatment Therapy that combines more than one method of treatment.
· mutation [mew tay´ shun] A change in the genetic material (DNA) inside the cell. Mutated genes might be inherited or caused by environmental exposure.
· myelin [my´ eh lin] The fatty substance that covers and protects nerves.
· myelogram [my´ eh low gram] An x-ray study of the spine using a special dye injected into the thecal sac. Commonly used before the widespread use of spinal MRI.
· myelosuppression [my´ eh low sue presh´ un] A decline or absence of blood cell production.
· myoclonic seizure [my o klon´ ick] A type of generalized seizure that causes single or multiple muscle twitches, jerks or spasms.
· myxopapillary ependymoma [mix o pap´ ih lair ee • ep en dih moe´ ma] A low grade ependymoma more commonly found in the spine than the brain.