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Breast cancer

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Gynecomastia is the enlargement of breast tissue in men. It is a common, benign condition that is caused by a change or imbalance in hormoneshormonesA substance that regulates specific body functions, such as metabolism, growth and reproduction. (testosterone, estrogen).

Obesity that causes the breasts to enlarge is called pseudogynecomastia. It is not caused by hormone imbalances.

Risk factors

Breast enlargement occurs mostly in young men during puberty and in older men. Both these age groups may have changes in their hormone levels.

The following risk factors may increase a man’s chance of developing gynecomastia:

  • a change or imbalance in hormone levels, especially during puberty or in older men
  • liver, kidney or thyroid disease
  • problems with the testicles
    • injury or trauma
    • twisting of the spermatic cord (testicular torsion)
    • inflammation
  • medications, such as those used to treat ulcers, high blood pressure and heart failure
  • drugs like anabolic steroids (used by some athletes and weightlifters)
  • a rare genetic condition called Klinefelter syndromeKlinefelter syndromeAn inherited sex chromosome disorder in which men have at least one extra X chromosome. Signs include small testicles, enlarged breasts and lack of facial and body hair.
    • Men with Klinefelter syndrome have an increased risk for developing breast cancer.

In rare cases, breast enlargement can occur because of tumours (such as testicular) or endocrineendocrineThe group of glands and cells in the body that make and release hormones (which control many functions such as growth, reproduction, sleep, hunger and metabolism) into the blood. gland disorders (including those that affect the adrenal or pituitary gland) that cause a man to produce more estrogen. Men normally produce some estrogen, but it is not enough to cause their breasts to grow.

Certain types of cancer can also increase the amount of hormones that may cause gynecomastia, including:

  • testicular cancer
  • lung cancer
  • stomach cancer
  • kidney cancer

Signs and symptoms

The signs and symptoms of gynecomastia may include:

  • enlargement of one or both breasts
  • tenderness
    • Breast pain in men is not usually a sign of cancer.


If the signs and symptoms of gynecomastia are present, or if the doctor suspects gynecomastia, tests will be done to make a diagnosis. Tests may include:


Treatment of gynecomastia will depend on the condition causing it. Finding and treating the underlying cause of the gynecomastia will often relieve this condition.

Breast enlargement during puberty may cause embarrassment and discomfort for teenage boys. In most cases, gynecomastia goes away without treatment after a period of time, usually within a few months.

Treatment options for gynecomastia may include:

  • supportive care – to treat pain and tenderness caused by breast enlargement
    • applying cold cloths to the breast
    • mild non-prescription pain medication
  • changing or stopping the drugs that may be causing the gynecomastia
  • more intensive treatments in the rare situations where gynecomastia does not go away on its own:
    • hormone therapy
    • breast reduction surgery or liposuction


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