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  • 06Sep

    Gynaecomastia – why breasts enlarge in males?

    The term gynaecomastia is derived from Greek words gyne (woman) and mastos (breast). An enlarged breast in a male is medically called gynaecomastia. It may be a normal phenomenon when it occurs temporarily during certain periods of life. This is called physiological gynaecomastia and is seen during neonatal period, adolescence and during old age. It is associated with an increased level of estrogen (female hormone) in blood in relation to testosterone (male hormone). 

    Gynaecomastia seen in the neonates (newborn babies) is called neonatal gynaecomastia. It occurs due to effect of placental estrogens on the breast tissue. During adolescence, the gynaecomastia occurs due to relative excess of estradiol in comparison to testosterone. With old age the blood level of testosterone drops resulting in a relative rise of circulating estrogen.

    Pathological changes in gynaecomastia

    On histological examination, it is seen that the ductal system of the male breast shows increased branching pattern with a concomitant increase in epithelium. Gynaecomastia may be classified according to the amount of glandular and fatty tissue. A purely glandular enlargement is called true gynaecomastia and a deposition of fat results in false or pseudogynaecomastia.  A mixed variety containing both fat and glandular tissue also exists.

    man1Clinical features

    With the development of secondary sexual characters during puberty (12 to 15 years of age), gynaecomastia may occur. It is usually unilateral (involving one side) or bilateral (both sides) and feels like a small nodule under the nipple. Gynaecomastia may or may not be associated with pain. The neonatal and senescent gynaecomastia is usually bilateral (involving both sides). The senescent gynaecomastia usually occurs in men aged 50 to 70 years. For clinical diagnosis, a breast nodule of at least 2 cm in diameter should be palpable. In obese people, mammography and ultrasonography is done to detect breast tissue.

    Clinical Classification of Gynaecomastia

    Grade I                  Mild breast enlargement without skin redundancy

    Grade IIa             Moderate breast enlargement without skin redundancy

    Grade IIb             Moderate breast enlargement with skin redundancy

    Grade III              Marked breast enlargement with skin redundancy and ptosis, which simulates

                               a  female breast

    Risk of breast cancer

    Though in general, gynaecomastia does not increase the risk of breast cancer; but its occurrence in association with Klinefilter’s syndrome (XXY), is associated with a risk for breast cancer. In this syndrome, which is characterized by hypoandrogenic state (low levels of male hormones), gynaecomastia occurs due to relatively higher estrogens. The cancer may be then detected on mammography or ultrasonography which may show dominant masses or areas of irregularity and asymmetry.

    Causes of breasts enlargement in males

    Gynaecomastia occurs due to relative or absolute excess of estrogens. It may be due to increased secretion by the testes, certain non-testicular tumours, endocrine disorders (hyperthyroidism or hypothyroidism), liver disease (cirrhosis due to alcohol, hepatitis B virus infection) and kidney failure.

    The lack of testosterone may be due to disorder of the testes. These include hereditary defects of male hormone production and congenital absence of testes (male eunuchs). Secondary failure of testes may result from injury, absence of testes from scrotum (undescended testes) and testicular inflammation (orchitis).

    Drug induced gynaecomastia is related to the intake of digitalis, estrogens, anabolic steroids  which increase estrogen levels or drugs acting against testosterone like cimetidine, ketoconazole, phenytoin, spironolactone, anticancer agents and diazepam.


    The treatment is indicated for cosmetic reasons and when cancer is suspected. Medical management may be tried initially and is based on hormonal manipulation depending on the cause; whether it is due to estrogen excess or androgen deficiency. The drugs available include testosterone, clomiphene, tamoxifen and danazol. Surgery is indicated for persistence despite 1 year of observation, failure of medical therapy, progressive size and persistence after puberty. Surgical treatments provided by plastic surgeons include liposuction and breast tissue excision (subcutaneous mastectomy).

    Gynaecomastia can be an embarrassing disorder in males and usually requires surgery for cosmetic reasons. A medical consult should be taken especially if it is unilateral, hard, irregular and progressive. Breast cancer in such situations should be ruled out.

    Anna L.

    It’s all about health!
    I have academic background in drugs related Chemical Technology, as well as extensive professional experience in pharma and medical companies. My main area of interest is everyday life medicine. The goal of my articles is to give people informative answers to the questions that bother them, to dispel doubts and some common misbeliefs and also to inspire everyone to keep healthy lifestyle.

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