Multiple primary cancers associated with endometrial and ovarian cancers: An analysis based upon the Japan Autopsy Annual Database from 2002 to 2010

Aim: A thorough analysis of multiple primary cancers (MPC) could provide important information as to the pathogenesis of human malignancies. Analysis of MPC using clinical databases has been performed, but little has been done using autopsy cases. Therefore, in this study, we first retrospectively analyzed MPC associated with endometrial and ovarian cancers using the Japan Autopsy Annual Database. Methods: The Japan Autopsy Annual Database from 2002 to 2010 was established by the Japanese Society of Pathology, Tokyo, Japan. Among the 164 211 autopsy cases registered, 9142 were cases of primary cancers. Results: The patients with endometrial cancer-associated MPC did have a lower risk of harboring colorectal cancer (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.45–0.89) but had a higher risk of ovarian cancer (OR, 3.15; 95% CI, 2.11–4.71). Those with ovarian cancer-associated MPC had a lower risk of harboring gallbladder cancer including bile ductal cancer (OR, 0.47; 95% CI, 0.27–0.80) but a higher risk of harboring breast (OR, 1.69; 95% CI, 1.20–2.38) and endometrial cancers (OR, 3.48; 95% CI, 2.33–5.20). Conclusion: Both endogenous and exogenous factors are associated with the incidence of MPC. Results of our present study based on Japanese Autopsy Base first demonstrated that female hormones had a strong influence on the incidence of MPC. This study also demonstrated that the analysis of MPC using an autopsy database could have advantages over clinical database analysis.