Diagnostic x-rays and risk of epithelial ovarian carcinoma in Jews.

Abstract

To test the hypothesis that there would be ethnic differences in susceptibility to ionizing radiation from diagnostic x-rays. In a hospital-based study we compared reports of diagnostic x-rays to the lower abdomen and pelvis in incident cases of epithelial ovarian carcinoma (N = 161), community controls (N = 156) and convenience controls (N = 87). Thirty-nine per cent of cases and 31% of controls recalled x-rays more than 10 years before; 27% of cases and 14% of controls reported four Jewish grandparents. Comparing the cases with community controls, the odds ratio (95% confidence interval) for Jews versus non-Jews among women reporting no x-rays was 1.02 (0.37-2.79); among women reporting x-rays the estimate for Jews was 8.91 (2.00-39.6). Consistent results were seen with inclusion of convenience controls. Jewish cases reported an excess of pelvic diagnostic x-rays from age 20 onward and an excess of barium enemas and pyelograms. These preliminary findings require confirmation in other studies. They suggest that the known excess risk of this carcinoma in Jews might be associated with exposure to x-rays and add to a previous observation of an altered susceptibility to ionizing radiation in Jews. If confirmed, they would suggest a need for continued vigilance to evaluate the risks and benefits of diagnostic x-rays in individuals, regardless of ethnic origin, who might carry mutations in DNA repair genes.