Abstract
Ovarian cancer (OC) and endometrial cancer (EC) are two female reproductive system tumors with high incidence rates. However, the clinicopathological characteristics of double primary OC and EC have been less studied. In this study, we aimed to identify some predictive and prognostic factors for synchronous endometrial and ovarian cancer (SEOC) by comparing survival outcomes between SEOC and single-primary OC patients.Clinical data were collected from 447 patients in the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed with OC as the first primary tumor and EC (8380/3, 8382/3, 8383/3) as the second primary tumor from 2010 to 2015. Survival outcome was estimated using Kaplan-Meier survival curves and compared using the log-rank test. Univariate and multivariate analyses were conducted utilizing COX models to identify their independent prognostic factors. A total of 447 SEOC patients and 20,769 single primary OC patients between 2010 and 2015 were included in this study. dual-primary group has more survival benefits than single-primary group. Age, marital status, histological typing, tumor size and tumor SEER stage and AJCC stage were independent factors affecting the prognosis of patients with double primary. Our study demonstrated that the clinicopathologic features of OC patients in the dual-primary group were young (43–55 years old), highly/moderately differentiated endometrioid ovarian cancer, and early-stage tumors. The prognosis of these patients was better than that of the single-primary group. These findings contribute to a better understanding of the differences between SEOC and single primary OC, and can help inform the development of more precise treatment guidelines to improve prognosis.