Incidence and treatment outcomes of ovarian sarcoma compared to epithelial ovarian cancer from the national cancer registry.

Abstract Purpose To investigate the incidence and survival outcomes of primary ovarian sarcoma compared to those of epithelial ovarian cancer. Methods Data on primary ovarian sarcoma patients (n = 1361) and epithelial ovarian cancer patients (n = 30,366) between 1999 and 2017 were obtained from the Korea Central Cancer Registry, and their respective age-standardized incidence rate (ASR) and relative survival rate were calculated and compared. Results Based on the ASR, the incidence of epithelial ovarian cancer was 4.75 per 100,000 women, while that of primary ovarian sarcoma was 0.22 per 100,000 women. The ASR ratio was 21.94 without significant change of ASR during the study period. Primary ovarian sarcoma had a better survival curve compared with epithelial ovarian cancer, though the difference was not statistically significant (5 yr overall survival 64.0% vs. 61.5%; p = 0.6030). In addition, among the pure sarcomas, the fibrosarcoma histologic subtype showed the best overall survival, and that of liposarcomas and stromal cell sarcoma were behind that (5 yr overall survival 85.0%, 76.7%, and 72.7%; p  Conclusions The incidence of primary ovarian sarcoma is quite low, with an ASR of 0.22/100,000 during the last 20 years. There were no significant differences between survival rates of primary ovarian sarcoma and epithelial ovarian cancer.