risk factors for male breast cancer identified

[Lani]

Risk Factors Associated with Male Breast Cancer Identified

Men who had a first-degree relative with breast cancer were at increased risk of developing the disease, as were those individuals who had a history of bone fracture, were obese, or had little physical activity.

Scientists have previously studied risk factors associated with male breast cancer in retrospective studies, which may be adversely influenced by participants' limited recall.

In the current study, published in the Journal of the National Cancer Institute, Louise Brinton, Ph.D., of the National Cancer Institute in Rockville, Md., and colleagues analyzed risk factors associated with male breast cancer in the prospective National Institutes of Health–AARP Diet and Health Study. A total of 324,920 men enrolled in the study and completed detailed questionnaires on lifestyle, diet, and medical and family history. Of those, 121 developed breast cancer.

Men with either a male or female first-degree relative with breast cancer had an increased risk of breast cancer compared with men who did not have an affected relative. Unexpectedly, a history of bone fracture was also associated with of an increased risk, an association that has not been seen in previous studies. An increased risk was also associated with obesity and a lack of physical activity, even after accounting for body mass. Alcohol consumption was not associated with risk of breast cancer in men.

"The identified risk factors show some commonalities with female breast cancer and indicate the importance of hormonal mechanisms. Differences in risk factors may reflect unique mechanisms associated with androgens and their ratio to bioavailable estrogens," the authors write.

SOURCE:
Journal of the National Cancer Institute, October 7, 2008