Physiology, Anatomy and Pathology of the Breast
The breast is biologically a gland that secretes sweat, it is a defining structure in mammals and its main function is to feed offspring. In humans, breasts have an added sexual component: female human breasts, in opposition to female primate breasts, maintain a considerable volume through out puberty, which can increase by one third during lactancy.
The mammary gland originates in the breast. Female breasts do not begin growing until puberty, moment in which breast skin also stretches to adapt to new shapes and sizes. Inside the breast, changes take place that prepare the mammary gland for lactancy: acinar cells, clustered in the lobules and which communicate to the outside through the galactophorous canals, suffer hypertrophy and activate, producing a typical secretion, which is milk. Hormone stimulation during menstruation, pregnancy and lactancy, as well as, hormone treatments and obesity, lead to a breast size increase.
The breast is formed early in fetal life from an invagination of the ectoderm (superficial layer) of the embryo’s ventral region. During this stage, some mammals develop two parallel rows (dogs, cats…), others such as humans, horses and bovine mammals only have two functioning mammary glands, the rest suffer atrophy. Nonetheless, some women present vestiges of these atrophied structures and more or less complete breasts are visible going from axilla to groin (supernumerary breasts or nipples).
Other possible anomalies are: complete absence of one or both breasts, important asymmetries (certain level of asymmetry is normal), alterations in nipple-areola complex (inverted nipples, hypertrophy, etc.), or breast growth in males (gynecomasty).
The aforementioned alternatives are mainly of morphological character.
We will not cover hispathological alterations, since they are not of special interest to our subject, but we can superficially highlight the most common pathologies: swelling (mastitis, abscesses and fat necrosis), hormones (benign mammary dysplasia, cysts and adenosis) and benign (fibroadenoma) or malign (carcinoma) tumors. Due to the frequency of alterations, an early diagnosis is vital. This implies periodic medical examinations and a well-informed patient, including breast self-examination and a periodic gynecological control.
Alteraciones estéticas de la mama
A young woman’s breast has a characteristic profile: upper portion makes a slight concave curve which ends at the areola. The lower portion likens the convexity of a drop of oil. Glandular breast tissue, fat and skin give the breast its shape. The skin itself functions as a natural bra.
Over the years, the loss of the elasticity of the skin, due to its individual characteristics and to repeated stretching (pregnancy and obesity), and the glandular breast tissue’s own weight, cause skin stretching and breast ptosis (sagging).
Through out the breast’s development and evolution alterations often appear due to volume excess (hypertrophies) or abscence of volume (atrophy, hypotrophy), unequal development (asymmetries) or malformations (tuberous breasts).