Risk factors

Factors that increase the risk of male breast cancer include:

• Older age. The risk of breast cancer increases as you age. Male breast cancer is most often diagnosed in men in their 60s.
• Exposure to estrogen. If you take estrogen-related drugs, such as those used for hormone therapy for prostate cancer, your risk of breast cancer is increased.
• Family history of breast cancer. If you have a close family member with breast cancer, you have a greater chance of developing the disease.
• Klinefelter's syndrome. This genetic syndrome occurs when boys are born with more than one copy of the X chromosome. Klinefelter's syndrome causes abnormal development of the testicles. As a result, men with this syndrome produce lower levels of certain male hormones (androgens) and more female hormones (estrogens).
• Liver disease. Certain conditions, such as cirrhosis of the liver, can reduce male hormones and increase female hormones, increasing your risk of breast cancer.
• Obesity. Obesity is associated with higher levels of estrogen in the body, which increases the risk of male breast cancer.
• Testicle disease or surgery. Having inflamed testicles (orchitis) or surgery to remove a testicle (orchiectomy) can increase your risk of male breast cancer.