Risk Factors for Male Breast Cancer
Male breast cancer is a rare disease, accounting for less than 1 percent of all breast cancer cases. Because of the low incidence of this disease, its cause and pathogenesis are not completely understood. Men are not routinely screened for the disease and usually do not think about the possibility of acquiring it. As a result, breast cancer, when first detected in a man, tends to be more advanced than when it is first diagnosed in women.
Scientists have discovered congenital, biological, and environmental factors that can increase risk of breast cancer in men. Some of these are related to sex hormone levels in the body. Risk factors include:
* Obesity: Fat cells in the body convert male hormones into female hormones, so that obese men have higher levels of estrogens in their bodies.
* Alcohol: Heavy alcohol intake increases the risk because of its effects on the liver.
* Liver disease: The liver plays an important role in sex hormone metabolism by making binding proteins that carry the hormones in the blood. Men with severe liver disease have relatively low levels of androgens and higher estrogen levels.
* Estrogen treatment: Men who take high doses of estrogens as part of a sex-change procedure or who take estrogen-related drugs to slow the growth of prostate cancer have a higher risk of breast cancer.
* Klinefelter syndrome: Men with this condition, which is present at birth, have more than one X (female) chromosome. They have lower levels of androgens and higher levels of estrogen, which causes the testicles to be smaller than usual and to not produce functioning sperm cells, making them infertile. Klinefelter syndrome affects about one in 1,000 men. …