AIMatMelanoma.org
en gb fr de es it iw el nl da fi sv no pl ru cs

Glossary


M

  • Macrometastases - Lymph node metastases that can be felt during medical examination or seen by the naked eye when inspected by a surgeon or pathologist.
  • Macrophages - Large white blood cells that engulf and digest antigens.
  • Magnetic Resonance Imaging (MRI) - A diagnostic technique in which magnetic fields create detailed, cross-sectional images of the body. An MRI may be used to see if melanoma has spread to lymph nodes or distant sites in the body.
  • Major Histocompatibility Complex (MHC) - Special marker proteins that, when linked to antigen fragments on an antigen-presenting cell, enable T-cells to recognize and neutralize the antigen. Cytotoxic T-cells recognize or "see" antigens in the context of MHC class I molecules. Helper T-cells recognize or "see" antigens in the context of MHC class II molecules.
  • Malignant - Cancerous; describing cells that can invade and destroy nearby tissue and spread to other parts of the body.
  • Malignant Melanoma - Melanoma that starts in the skin; also called cutaneous melanoma.
  • Margin - Refers to the amount of normal-appearing tissue to be removed along with the tumor during surgical excision. The margin is usually measured in centimeters. The deeper the Breslow Depth of a primary melanoma the wider the recommended margins will be.
  • Matted - Connected.
  • Mediastinum - The space in the chest cavity located between the lungs containing the heart and its large blood vessels, the trachea, the esophagus, the bronchi, and the lymph nodes.
  • Medical Oncologist - A physician who specializes in the diagnosis, treatment, and management of cancer using chemotherapy, biological therapy, and hormone therapy. Medical oncologists are specialists in internal medicine and often coordinate the cancer treatment provided by other specialists.
  • Melacine - A manufactured allogeneic vaccine derived from tumor lysates.
  • Melanin - The pigment protein that gives color to the skin, hair, and parts of the eye and provides protection against the damaging effects of ultraviolet radiation by absorbing energy from UV light.
  • Melanocytes - Specialized pigment-producing cells located primarily at the bottom of the epidermis that create and transfer pigment to other skin cells and is responsible, at least in part, for skin and hair color.
  • Melanoma - A type of cancer that arises in melanocytes, the cells that produce melanin. Melanoma occurs most often in the skin but may also develop in the eye or the lining of the nose, mouth, or genitals. Melanoma is the least common but most deadly skin cancer, accounting for only about 4% of all classes but 79% of skin cancer deaths.
  • Melanoma in situ (Latin for "in place") - Very early-stage melanoma where the tumor is limited to the epidermis with no invasion of surrounding tissues, lymph nodes, or distant sites. It has the best long term prognosis of any melanoma.
  • Melanoma-Inhibiting Activity (MIA) - A protein secreted by malignant melanoma cells and being investigated as a tumor marker.
  • Melphalan - Chemotherapy agent used in isolated limb perfusion.
  • Metastasis - The spread of cancer from its site of origin to other parts of the body.
  • Metastatic Melanoma - Melanoma that has spread to other parts of the body by way of the bloodstream or the lymphatic system.
  • Micrographic Surgery (Mohs Surgery) - A specialized surgical technique in which all visible tumor is excised and then, while the patient waits, the skin is examined under a microscope. If cancer is found to persist, the surgeon then removes more skin, only in that area, and again examines the tissue while the patient waits. The process is repeated until all the cancer is removed. Mohs surgery is used to treat basal- and squamous-cell carcinoma and can be used to treat early-stage melanoma. It is used when the primary tumor is located on the face or another area where it is essential to preserve as much healthy tissue as possible.
  • Micrometastases - Tiny lymph node metastases that can only be detected by microscopic evaluation.
  • Mitoses - Refers to cancer cells in the process of dividing. Mitoses can be counted by a pathologist when examining tissue with a microscope. The number of mitoses in an area of a pathological specimen correlates with the rate of cell division.
  • Mitotic Rate (Mitotic Count) - Pathologists count the average number of cells dividing in a melanoma specimen and use this to determine the mitotic rate. Higher mitotic rates are associated with more rapidly dividing cells and a greater potential for metastasis. Because the mitotic rate has been proven to provide prognostic data, in 2010 the AJCC recommended that mitotic rate be used in determining the stage of thin (Stage I) primary melanomas.
  • Mole - A pigmented skin growth formed primarily by a cluster of melanocytes and surrounding supportive tissue. The scientific name for a mole is a melanocytic nevus. Moles usually appear as tan, brown, or flesh-colored spots on the skin.
  • Monoclonal Antibodies - Manufactured antibody proteins, types of which originate in laboratory animal or humans. When injected into the body, they are able to recognize antigens for various medical purposes. Monoclonal antibodies can locate and attach to cancer cells with specific antigens, either to identify them for diagnostic purposes or to kill them in therapy. They may be used alone or to deliver radiation, chemotherapy, or other biological therapies more directly to a tumor.
  • Mortality Rate - Ratio of the number of deaths to a given population each year.
  • Mutation - A permanent change in the structure of DNA that, if not corrected by the cell, can be passed on to subsequent cells. Mutations that occur in critical areas of the DNA that correlate to the genes that control how often a cell divides can eventually cause the cell to become cancerous.