Gynecomastia

Gynecomastia (also spelled Gynaecomastia) is an endocrine system disorder in which a noncancerous increase in the size of male breast tissue occurs. Psychological distress or dysphoria may occur. The development of gynecomastia is usually associated with benign pubertal changes. However, 75% of pubertal gynecomastia cases resolve within two years of onset without treatment. In rare cases, gynecomastia has been known to occur in association with certain disease states. The pathologic causes of gynecomastia are diverse and may include Klinefelter syndrome, certain cancers, endocrine disorders, metabolic dysfunction, various medications, or may occur due to a natural decline in testosterone production. Disturbances in the endocrine system that lead to an increase in the ratio of estrogens/androgens are thought to be responsible for the development of gynecomastia. This may occur even if the levels of estrogens and androgens are both appropriate, but the ratio is altered. Diagnosis is based on signs and symptoms. The condition commonly resolves on its own and conservative management of gynecomastia is often all that is necessary. Medical treatment of gynecomastia that has persisted beyond two years is often ineffective. Medications such as aromatase inhibitors have been found to be effective in rare cases of gynecomastia from disorders such as aromatase excess syndrome or Peutz–Jeghers syndrome, but surgical removal of the excess tissue is usually required. Gynecomastia is common. Physiologic gynecomastia develops in up to 70% of adolescent boys. Newborns and adolescent males often experience temporary gynecomastia due to the influence of maternal hormones and hormonal changes during puberty, respectively. The classic feature of gynecomastia is male breast enlargement with soft, compressible, and mobile subcutaneous chest tissue palpated under the areola of the nipple in contrast to softer fatty tissue. This enlargement may occur on one side or both. Dimpling of the skin and nipple retraction are not typical features of gynecomastia. Milky discharge from the nipple is also not a typical finding, but may be seen in a gynecomastic individual with a prolactin secreting tumor. An increase in the diameter of the areola and asymmetry of chest tissue are other possible signs of gynecomastia. Males with gynecomastia may appear anxious or stressed due to concerns about the possibility of having breast cancer. Gynecomastia is thought to be caused by an altered ratio of estrogens to androgens mediated by an increase in estrogen production, a decrease in androgen production, or a combination of these two factors. Estrogen acts as a growth hormone to increase the size of male breast tissue. The cause of gynecomastia is unknown in around 25% of cases. Drugs are estimated to cause 10–25% of cases of gynecomastia. Certain health problems in men such as liver disease, kidney failure, or low testosterone can cause breast growth in men. Drugs and liver disease are the most common cause in adults. Other medications known to cause gynecomastia include methadone; aldosterone antagonists (spironolactone and eplerenone); HIV medication; cancer chemotherapy; hormone treatment for prostate cancer; heartburn and ulcer medications; calcium channel blockers; antifungal medications such as ketoconazole; antibiotics such as metronidazole; tricyclic antidepressants such as amitriptyline; and herbals such as lavender, tea tree oil, and dong quai. The insecticide phenothrin possesses antiandrogen activity and has been associated with gynecomastia.