Gynecomastia is the term used to describe the benign growth of glandular breast tissue in men. The most common causes are pubertal gynecomastia, hypogonadism, and drugs. An imbalance in the actions of free estrogen and androgens in the breast tissue is the root cause of gynecomastia. Physiologic or pubertal gynecomastia is a common finding in mid-puberty, with pubic hair present in Tanner stage III–IV. Gynecomastia is commonly bilateral, however, 20% of pubertal boys have unilateral disease. In gynecomastia, evaluation needs history – onset, progression, associated pain, medication history, and symptoms of hypogonadism. True gynecomastia and pseudogynecomastia should be distinguished by the feel of glandular or fat tissue. The testis and abdomen examination is an essential part of the examination. It is reasonable to measure the levels of serum testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), prolactin, thyroid stimulating hormone (TSH), serum estradiol, serum human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP), liver function test, and renal function test in peripubertal boys with macromastia (Tanner stage III or greater) and adult males with newly developing gynecomastia, fast growth, and eccentric or hard, irregular masses or gynecomastia larger than 4 cm inch. Physiologic gynecomastia usually resolves on its own. In 75–90% of adolescents, pubertal gynecomastia resolves independently after 1–2 years. Aromatase inhibitors, e.g., letrozole and estrogen receptor modulators, e.g., tamoxifen (10–20 mg daily), are recommended for painful pubertal gynecomastia or macromastia (Tanner staging III or more). If the gynecomastia is persevering (>2 years) and very disturbing to the boy, surgical reduction, mammoplasty by an experienced surgeon can be pursued.
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