X-rays may greatly raise the risk of breast cancer in women who are genetically susceptible to the disease, researchers reported on June 26. A study of women with genetic mutations known to cause breast cancer showed that having a chest X-ray could double or even triple that risk.
The findings are not clear-cut and not clear what kind of chest X-rays pose the greater risk, said Dr David Goldgar of the University of Utah School of Medicine, who helped lead the research.
The researchers looked only at women who have a certain version of the BRCA1 and BRCA2 breast cancer genes, known to raise the risk of both ovarian and breast cancer.
"The results from this study raise potentially significant clinical considerations," the researchers wrote in a report, published in the Journal of Clinical Oncology. "The absolute risk of breast cancer by age 50 years is in the order of 40 percent in BRCA1 carriers and 15 percent in BRCA2 carriers."
Women exposed to X-rays before age 20 had a 2.5-fold increased risk of developing breast cancer before age 40, compared with those who had never had a chest X-ray.