Does mammography increase breast cancer risk in some women?

Radiation from mammograms and x-rays may increase the risk for developing breast cancer in young women who are already at highest risk for the disease-those with BRCA1 or BRCA2 mutations-and those with a familial predisposition, according to the findings of a recent study from the Netherlands.

The study included pooled data on about 12,000 high-risk women from the United States and Europe who had participated in 6 previous peer-reviewed studies (median age, 45 years).

Researchers found that the risk for breast cancer was 1.5 times greater among the high-risk women who had been exposed to low-dose radiation (ie, mammograms or chest x-rays) than among the unexposed high-risk women. In addition, high-risk women exposed to low-dose radiation before the age of 20 and those with 5 or more exposures were 2.5 times more likely to develop the disease than were other high-risk women who had not been exposed to radiation.

These findings do not pertain to women with average risk for developing breast cancer.

Greuter MJ, Jansen-van der Weide MC, Jacobi CE, et al. The validation of a simulation model incorporating radiation risk for mammography breast cancer screening in women with a hereditary-increased breast cancer risk. Eur J Cancer. 2009. Epub ahead of print. doi:10.1016/j.ejca.2009.10.030.