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The term breasts can refer to the upper ventral region of the human torso. Alternatively the term is used for each of two parts of that, especially for women: the breasts are parts of the female human body that contain the organs that secrete milk used to feed infants. Males also have breasts and are born with the main milk ducts intact, but while the gland that produces milk is present in the male, it normally remains undeveloped. In some situations male breast development does occur, a condition called gynecomastia. Milk production can also occur in both men and women as a rare side-effect of some medicinal drugs (such as some antipsychotic medication). Both sexes have a large concentration of blood vessels and nerves in their nipples.
A woman's breasts sit over the pectoralis major muscle and usually extend from the level of the 2nd rib to the level of the 6th rib anteriorly. The superior lateral quadrant of the breast extends diagonally upwards in an 'axillary tail'. A thin layer of mammary tissue extends from the clavicle above to the seventh or eight ribs below and from the midline to the edge of the latissimus dorsi posteriorly.
Important parts of the breasts include mammary glands, the axillary tail (tumours are most likely to occur here), the lobules, Cooper's ligaments, the areolaIn anatomy, the term areola is used to describe any small circular area such as the dark skin surrounding the nipple. While it is most commonly used to describe the pigmented ring around the human nipple, it can also be used to describe other small circul and the nipple.
As breast cancerBreast cancer is cancer of breast tissue. Worldwide, it is the most common form of cancer in females, affecting approximately 10% of all women at some stage of their life in the Western world. Although significant efforts are made to achieve early detecti is a common cancerFor other meanings of Cancer: see Cancer (disambiguation . apoptosis; cancer cells, however, avoid apoptosis. Cancer is a group of related diseases characterized by uncontrolled cell division. Currently, it is believed that cancers arise from both genetic, the lymphatic drainage of the breast (sites where cancer may metastasizeMetastasis is the spread of cancer from its primary site to other places in the body. Localised spread to lymph nodes is not normally counted as metastasis, although this is a sign of poor prognosis. Cancer cells can break away from a primary tumor, penet) is important.
About 75% of lymph from the breast travels to the ipsilateral (same side) axillary lymph nodeLymph nodes are components of the lymphatic system. Clusters of lymph nodes are found in the underarms, groin, neck, chest, and abdomen. Lymph nodes act as filters, with an internal honeycomb of connective tissue filled with lymphocytes that collect and ds. The rest travels to parasternal nodes, to the other breast, or abdominal lymph nodes.
The axillary nodes include the pectoral, subscapular, and humeral groups of lymph nodes. These drain to the central axillary lymph nodes, then to the apical axillary lymph nodes.