Enlarged male breasts can be enlarged on one side or both sides, which is not uncommon clinically. Some male breasts can be enlarged to a large size, like a full woman’s breasts, and they dare not wear a tank top in summer. There is usually tenderness, and sometimes there is a milk-like discharge from the nipple. Patients worry a lot about this, wondering if they are feminizing or suspecting that they have a tumor in the breast area, and also struggling with how to treat it. Today we will talk to you about this strange and untold disease. The development of breasts depends on the secretion of estrogen. Under normal physiological conditions, men have a small amount of estrogen in addition to androgen in their bodies, really like what Zhao Benshan said in his skit, “Half of a man is a woman”. However, androgens and estrogens normally maintain a dynamic balance (androgen/estrogen ratio), which is like the warp board in the park, where this side is high and the other side is low. If estrogen increases in men, male breasts will increase in size. Enlarged breasts in men are medically known as gynecomastia or male breast enlargement. There are many factors that can cause gynecomastia, either physiological, caused by taking some medications, or of course, pathological. Male breast enlargement in infancy, adolescence and old age is mostly physiological.1. Infancy: male infantile breast enlargement in infancy may be due to the effect of maternal placental estrogen on infant breast development, which generally lasts only a few weeks.2. Adolescence: according to statistics, about 2/3 of adolescent males develop mastopexy, with a high incidence at the age of 14-15. Adolescent male breast enlargement is due to the synthesis of estrogen prior to the secretion of large amounts of testosterone by the testes, which promotes the formation of gynecomastia.3. Old age stage: After entering old age, testosterone in the blood decreases, while estrogen (luteinizing hormone) rises, the dynamic balance of androgen/estrogen in the plasma is broken, and the androgen/estrogen ratio decreases. This leads to enlargement and development of the breast in older men. All three of these conditions are considered clinically normal physiological phenomena and are referred to as physiological male breast enlargement. Pathological gynecomastia is more complex and is the focus of our attention. It is mainly caused by certain diseases or certain drugs that cause insufficient production of androgens (testosterone) or their weakening, or excessive production of estrogen. (1) Patients suffering from diseases with low androgen secretion or receptor insensitivity to androgens: such as Klinefelter’s syndrome, anencephaly, androgen insensitivity syndrome, etc., due to low androgen levels, which increase pituitary gonadotropin secretion or androgen insensitivity to receptors, the ratio of estrogen to androgen is imbalanced, thus leading to mastocytosis. (2) Clonal karyotype abnormalities: Some male breast development is due to clonal karyotype abnormalities, such as 12p deletion, chromosome 9, 17, 19 and 20 monosomy, and some patients are accompanied by benign or malignant tumors of the breast. (3) Diseases leading to imbalance of androgen and estrogen balance: such as liver cirrhosis, alcoholism, etc. As the liver function decreases, the degradation and inactivation of estrogen by the liver is weakened. Then estrogen is relatively increased. ② Hyperthyroidism: About 10% of male patients with hyperthyroidism also suffer from mastocytosis. The cause is unknown, but mastocytosis in men improves greatly when anti-hyperthyroidism is effective. (iii) Chronic renal failure. The accumulation of toxic substances that cannot be excreted from the body inhibits the testosterone secretion function of the testes, resulting in a decrease in blood testosterone levels and an increase in prolactin hormones with an increase in lactogen. This causes male breast enlargement. ④ Malnutrition. It can lead to insufficient androgen synthesis and inhibition of pituitary gonadotropin synthesis and secretion. When nutrition improves, this inhibition is then lifted. (4) Increased estrogen production: For example: ① Testicular tumors. For example, testicular choriocarcinoma, testicular teratoma and a few testicular seminoma can produce chorionic gonadotropin, which can increase the synthesis of testosterone and estradiol in testicular tissue not invaded by tumors. (ii) Tumors of the adrenal glands. Some adrenal carcinomas can produce large amounts of estrogen or its precursors – androstenedione and other substances, which in turn can be converted into estradiol by aromatase in the surrounding tissues, while pituitary gonadotropin secretion is suppressed and testosterone secretion is reduced in patients. (6) Drug effects: For example: ① The application of estrogen due to prostate cancer, or frequent exposure to estrogen in industrial production, frequent consumption of estrogen-containing foods, or even long-term use of estrogen-containing cosmetics can lead to male breast hyperplasia. In addition, the cardiotonic drug digitalis also has a slight estrogenic effect. ②Chorionic gonadotropin can cause the testes to increase the secretion of estradiol and testosterone, and long-term use can lead to the development of breast enlargement. (iii) Androgen antagonists. For example, cyproterone flutamide can inhibit the binding of testosterone to the receptor. Other agents such as cimetidine and spironolactone inhibit the synthesis of testosterone by inhibiting the action of 17,20 lyase, resulting in a decrease in androgens. ④ Long-term androgen users. Excess androgens can be converted into estrogens through the action of aromatase, which can promote breast enlargement and development. ⑤ Some drugs, such as isoniazid, rifampin, Maryland, calcium antagonists, ACE inhibitors, phenytoin sodium, penicillamine, diazepam; the drugs marijuana, heroin, etc. The exact mechanism of action of these drugs is unknown. In addition, surgery resulting in the removal of the testicles, or radiation therapy with chemotherapy resulting in impaired testicular function, which causes a decrease in testosterone production, can also cause gynecomastia. Now we know that gynecomastia is a benign disease of the breast, not a tumor! So does gynecomastia need to be treated? How can it be treated? Most patients with gynecomastia do not need treatment, especially since adolescent gynecomastia has a high degree of self-limitation. Most patients disappear on their own within 1 to 2 years of onset. If the enlargement is due to estrogen, it will gradually subside after stopping. If there are more severe symptoms such as pain, you can take methyltestosterone orally 3 times a day at 5mg each time, which can be taken continuously for about one month and can be basically relieved. Some male breast enlargement needs to be treated surgically. Indications for surgery: (1) if the enlargement of the breast is obvious and affects the beauty and does not subside within 2 years; (2) if medication is ineffective; (3) if there are symptoms such as swelling and pain; (4) if cancer is suspected. Furthermore, surgery should be considered only if the patient requires surgery. The purpose of surgery is to remove the hyperplastic glands and excess skin (including some with malignant cancerous lumps), thereby reducing the size of the breast and restoring it to the normal size and aesthetically pleasing side, thus removing the patient’s worries. We use a small incision through the areola or under the areola to remove the enlarged glandular tissue, and at the same time perform nipple remodeling, skin reconstruction and cosmetic suturing of the incision to make the surgical site beautiful and scarless.