Gynaecomastia

Enlargement of one or both breasts in the male, due, in some cases, to an excess of the female sex hormone oestrogen in the blood. Mild, temporary gynaecomastia can occur at birth as a result of maternal hormones, and it is common at puberty. Gynaecomastia developing in later life may be due to chronic liver diseases such as cirrhosis. Hormone secreting tumours such as pituitary or testicular tumours may also be a cause. Adult gynaecomastia, which sometimes occurs in only one breast, can also occur when synthetic hormones and some drugs, such as digoxin, spironolactone, and cimetidine, change the balance of sex hormones. Rarely, a discrete lump that develops on one breast may be due to a male breast cancer. Investigation may involve blood tests. If cancer is suspected, a biopsy will be performed. Treatment depends on the cause. If a drug is responsible, an alternative will be prescribed if possible. If there is no underlying disease, swelling usually subsides without treatment. Cosmetic surgery may be considered in severe cases (see mammoplasty).