Trends in Gynecologic Carcinosarcoma Based on Analysis of the Surveillance Epidemiology End Result (SEER) Database

Carcinosarcomas (malignant mixed Mullerian tumors) of a female genital organ are rare tumors associated with a poor survival. The purpose of this study was to identify site-specific differences in the incidence and prognosis in carcinosarcomas originating in the uterus, cervix, or ovary. The data of patients with gynecologic carcinosarcomas were extracted from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2016. The characteristics of gynecologic carcinosarcomas were compared using Pearson X2 and Fisher's exact tests. Kaplan-Meier models were used for cause-specific survival (CSS) analysis. The cohort included 7086 females, including 5731 cases of uterine carcinosarcoma, 161 cervical carcinosarcomas, and 1193 ovarian carcinosarcomas. The age-adjusted incidence rates of uterine, cervical, and ovarian carcinosarcoma were 3.9, 0.1, and 0.6 per 1,000,000, respectively. In the distribution of carcinosarcoma incidence by race, compared with the uterus or cervix, those originating from the ovary were unequally distributed in Caucasians (84.4% versus 69.6%, 67.7%; p < 0.001). The incidence of uterine carcinosarcoma steadily increased over time, from 2.2 in 2000 to 5.5 in 2016 (per 1,000,000), while cervical or ovarian carcinosarcoma showed no significant difference in incidence. The five-year CSS rates based on the site of origin (uterus, cervix, and ovary) were 39.9%, 33.1%, and 25.8%, respectively. The incidence rates of gynecologic carcinosarcoma, especially uterine carcinosarcoma, are gradually increasing. Although uterine carcinosarcoma is associated with a higher incidence than the others, it has a better prognosis compared with ovarian and cervical carcinosarcoma. The survival rates were worst in ovarian carcinosarcoma.