Risk factors
By Mayo Clinic staffFactors that increase the risk of male breast cancer include:
- Older age. Breast cancer is most common in men ages 60 to 70.
- Exposure to estrogen. If you take estrogen-related drugs, such as those used as part of a sex-change procedure, your risk of breast cancer is increased. Estrogen drugs may also be used in hormone therapy for prostate cancer.
- 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 a boy is 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. If you have liver disease, such as cirrhosis of the liver, your male hormones may be reduced and your female hormones may be increased. This can increase your risk of breast cancer.
- Obesity. Obesity may be a risk factor for breast cancer in men because it increases the number of fat cells in the body. Fat cells convert androgens into estrogen, which may increase the amount of estrogen in your body and, therefore, your risk of breast cancer.
- Radiation exposure. If you've received radiation treatments to your chest, such as those used to treat cancers in the chest, you're more likely to develop breast cancer later in life.
References
- Male breast cancer treatment (PDQ). National Cancer Institute. http://www.cancer.gov/cancertopics/pdq/treatment/malebreast/patient. Accessed Jan. 18, 2012.
- Johansen Taber KA, et al. Male breast cancer: Risk factors, diagnosis and management. Oncology Reports. 2010;24:1115.
- Gomez-Raposo C, et al. Male breast cancer. Cancer Treatment Reviews. 2010;36:451.
- Brain K, et al. Psychological distress in men with breast cancer. American Journal of Clinical Oncology. 2006;24:95.
- Distress management. Fort Washington, Pa.: National Comprehensive Cancer Network. http://www.nccn.org/professionals/physician_gls/f_guidelines.asp. Accessed Jan. 18, 2012.


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