Dictionary

mastoid The rounded protrusion of bone just behind the ear. The mastoid was once thought to look like a breast (hence its name).

mastocytosis A condition characterized by infiltration of mast cells into the tissues of the body. Mast cells are connective tissue cells which release chemicals, including histamine, that cause itching, swelling, and fluid leakage from cells. There are several different clinical forms of mastocytosis. See also mast cell; mastocytoma.

mastocytoma A benign nodular tumor on the skin, rich in mast cells, that is usually present at birth or in early childhood and resolves spontaneously. Also called a mast cell tumor. See also mast cell.

mastitis Inflammation of one or more mammary glands within the breast, usually in a lactating woman. Mastitis can be felt as a hard, sore spot within the breast. Mastitis can be caused by an infection in the breast or by a plugged milk duct. Treatment includes resting and applying warm compresses to the affected area,…

mastectomy, total A simple mastectomy. See mastectomy, simple.

mastectomy, subcutaneous Removal of breast tissue, using a minimal incision. This type of mastectomy may be used to remove small areas of suspicious or cancerous tissue, but it can also be a cosmetic surgery procedure. For example, subcutaneous mastectomy can reduce the volume of enlarged male breasts or be part of a female-tomale sex-change procedure.

mastectomy, simple Removal of one or both breasts, but not the lymph nodes. Also known as a total mastectomy.

mastectomy, segmental A partial mastectomy. See mastectomy, partial.

mastectomy, radical Removal of all breast tissue, from just under the collarbone to the abdomen, including the chest wall muscles and the axillary lymph nodes in the armpit. In a trial begun in 1971, the efficacy of radical mastectomy was compared with that of total mastectomy. This historic trial spelled the end of radical mastectomy…

mastectomy, prophylactic See mastectomy, preventive.

mastectomy, preventive Removal of one or both breasts without the current presence of cancer. This surgery is sometimes chosen as a preventive measure by women who have a strong family history of breast cancer.

mastectomy, partial Surgical removal of only enough breast tissue to be sure that the margins of the tissue removed are free of cancer. Also known as segmental mastectomy.