Prognosis of women with stage I endometrioid endometrial cancer and synchronous stage I endometrioid ovarian cancer

Synchronous endometrial and ovarian cancer with endometrioid histology at two cancer sites typically presents with early-stage disease and is thought to have a good prognosis. We examined the survival of women with early-stage endometrioid endometrial cancer who had synchronous early-stage endometrioid ovarian cancer. This is a retrospective case-control study examining the Surveillance, Epidemiology, and End Result Program between 1973 and 2013. Survival of women with stage I endometrioid endometrial cancer with stage I endometrioid ovarian cancer (n=839) were compared to women with stage I endometrioid endometrial cancer without synchronous ovarian cancer (n=123,692) after propensity score matching. Women with synchronous stage I endometrioid ovarian cancer were more likely to be diagnosed recently, be younger, have stage IA disease, grade 1 tumors, to have undergone lymphadenectomy, and were less likely to receive radiotherapy compared to those without synchronous ovarian cancer (all, P