Gynecomastia

Gynecomastia is the proliferation of benign male glandular breast tissue. It may be unilateral or bilateral, painful, or asymptomatic.

Gynecomastia results from excessive estrogen action or deficient testosterone action on breast glandular tissue.

Physiologic gynecomastia occurs in the newborn period, during puberty, and with aging and obesity.

Many drugs, environmental exposures, illnesses, and some genetic conditions increase the risk for gynecomastia. Treatment may improve gynecomastia, especially if it is of recent onset.

Most cases require no specific treatment. Therapies for persistent pain or psychological distress include anti-estrogen therapy, androgen replacement if proven testosterone deficiency, or surgery (liposuction or mammoplasty).

Gynecomastia is the benign enlargement of the male breast glandular tissue with firm tissue extending concentrically beyond the nipple. Histologically, gynecomastia is the benign proliferation of breast ducts and duct epithelial hyperplasia accompanied by varying amounts of inflammation, edema, stroma, and fibrosis. Male breast enlargement entirely due to adipose tissue is called pseudogynecomastia.[Figure caption and citation for the preceding image starts]: Histology: gynecomastia; clusters of ducts, halos of edema, fibrous background; 5X magnificationFrom the collection of Catherine B. Niewoehner, MD [Citation ends].