Radiation exposure linked to male breast cancer

In a study of Japanese atomic bomb survivors, male subjects exposed to radiation were more likely than their unexposed peers to develop breast cancer.

The new findings add to earlier reports suggesting that radiation exposure raises the risk of male breast cancer, lead author Dr. Elaine Ron, from the National Cancer Institute, Bethesda, Maryland, and colleagues note.The current study, reported in the Journal of the National Cancer Institute for April 20th, involved 32,411 male subjects who were exposed to a known radiation dose, 2978 exposed to an unknown dose, and 10,491 unexposed subjects. Nine men exposed to radiation developed breast cancer, yielding a crude rate of 1.8 cases per 100,000 person-years. By contrast, three men in the unexposed group developed this malignancy, yielding a significantly lower crude rate of 0.5 cases per 100,000 person-years.In addition, the authors found that the risk of male breast cancer was directly related to the dose of radiation received (p = 0.01).”Because male breast cancer is a rare disease, few cases were seen in this 40-year follow-up of a large cohort,” the researchers point out. “However, the results clearly show an association between exposure to external radiation and the occurrence of male breast cancer.”(Source: J Natl Cancer Inst 2005;97:603-605: Reuters Health: Oncolink: May 2005.)