Picture of Gynecomastia

Gynecomastia, male breasts, of a 63 year old man. Gynecomastia is usually due to abnormally high levels of the female hormone estrogen in the blood. Many conditions can cause this, such as liver cirrhosis (where the liver cannot break down the natural estrogen present), tumors (usually involving the testes, adrenal glands, pituitary, lung and liver) and certain medications. Treatment therefore depends on the underlying cause. The swelling often subsides naturally, although breast reduction surgery can also be performed.
Source: Dr. P. Marazzi / Science Source