Gynecomastia ( English American) or Gynaecomastia (English British )
is the growth of abnormally big breasts on men. It
comes from the Greek word Gyne meaning "woman" and Mastos meaning
"breast". The condition can occur physiologically in
adolescents, in neonates, and in older men. In most adolescent boys the symptoms
will disappear in a few months to a couple years at
most. It is usually just a result of an imbalanced hormones, although
there can be many different causes. Gynecomastia is not just a
buildup of adipose tissue, it also includes development of glandular
Physiologic gynecomastia occurs in neonates, with aging and in
Potential pathologic causes of gynecomastia are: increased serum
estrogen, androgen receptor defects, medications
including hormones, decreased testosterone
production, chronic kidney disease,
HIV, chronic liver disease, and other chronic illness. Gynecomastia
as a result of spinal cord injury and refeeding after starvation has
been reported. In 25% of cases, the cause of the gynecomastia is unknown.
Medications cause over 15% of cases of gynecomastia. These include spironolactone, cimetidine, finasteride, omeprazole and
some antipsychotics. They can act directly on the breast tissues, while
lead to increased secretion of prolactin from the pituitary by
blocking the actions of dopamine (PIF/Prolactin-Inhibiting Factor)
on the lactotrope cell groups in that organ. Androstenedione, used
as a performance enhancing food supplement, can lead to breast
enlargement by excess estrogen activity. Marijuana usage is
thought to be another possible cause.
Increased estrogen levels can also occur with certain testicular
tumors, and in hyperthyroidism. Certain adrenal tumors cause
elevated levels of androstenedione which is converted by the enzyme
aromatase into estrone, a type of estrogen. Other tumors that
secrete hCG can increase estrogen. A decrease in estrogen clearance
can occur in liver disease, and this could be the mechanism of
gynecomastia with liver cirrhosis. Obesity can also increase estrogen
Decreased testosterone production can occur with congenital or
acquired testicular failure, for example in genetic disorders like Klinefelter Syndrome. Diseases of the
pituitary or hypothalamus
can also lead to low testosterone. Abuse of anabolic steroids has a
Although stopping these medications can lead to regression of gynecomastia, surgery is sometimes
needed to eliminate the
This condition can usually be diagnosed by a
physician. Occasionally, imaging by ultrasound or X-rays is needed
to confirm diagnosis. Blood tests are required to see if there
is any underlying disease causing the gynecomastia.
Gynecomastia is not physically harmful, but in a few cases it is an
indicator of more dangerous underlying conditions.
Gynecomastia presents social and psychological
difficulties for the sufferer. Weight loss can alter the condition
in cases where it is triggered by obesity, but for many it will not
eliminate it as the breast tissue remains.
Treating the underlying cause of the gynecomastia may lead to
improvement in the condition. Patients should stop taking medications
which can cause gynecomastia. Anti-estrogen medications, such as
clomiphene and tamoxifen or androgens can be used. Aromatase
inhibitors are another treatment option, although they are not
universally approved for the treatment of gynecomastia.
Endocrinological attention may help during the first 2-3 years.
After that window, however, the breast tissue tends to remain and
harden, leaving surgery (either liposuction or reduction mammoplasty)
the only treatment option. Radiation therapy is often used to
prevent gynecomastia in patients with prostate cancer before
estrogen therapy. Some men choose to live with the condition and
wear a bra for support.
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