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Gynecomastia : Causes

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Introduction: Gynecomastia is enlargement of male breast due to hyperplasia and hypertrophy of both glandular and stromal compartments.

Causes: The underlying pathophysiology in many causes of gynecomastia is increased estrogenic activity (endogenous or exogenous), reduced androgenic activity, or a combination of both. Gynecomastia before age 25 is related to hormonal changes at puberty. The causes of gynecomastia in later life include hormonally-active tumors (Leydig cell tumors of testis, hCG-secreting testicular germ cell tumors, and lung cancer), cirrhosis, and drugs (digitalis, reserpine, phenytoin). Rare cases of neurofibromatosis 1 are associated with gynecomastia. Many cases are idiopathic. Neonates may have gynecomastia due to in utero action of maternal and placental estrogens.

Clinical Features: Gynecomastia usually involves breast tissue behind nipple. In contrast, carcinoma of male breast tends to be located eccentrically. It may be unilateral (L>R) or bilateral. Hormone-induced gynecomastia is usually bilateral, where as drug-induced (nonhormonal) is usually unilateral.

The photograph shows bilateral gynecomastia in a 69 y/o male. Case courtesy of: Dr. Sanjay D. Deshmukh, Professor of Pathology, Vithalrao Vikhe Patil Foundation's Medical College & Hospitals, Ahmednagar, India.

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