Uterine carcinosarcoma vs endometrial serous and clear cell carcinoma: A systematic review and meta-analysis of survival

Background It is unclear whether uterine carcinosarcoma (UCS) is more aggressive than endometrial serous carcinoma (SC) and clear cell carcinoma (CCC). Objectives To compare the prognosis of UCS to that of endometrial SC and CCC, through a systematic review and meta-analysis. Methods Four electronic databases were searched from January 2000 to October 2020. All studies assessing hazard ratio (HR) for death in UCS vs SC and/or CCC. HRs for death with 95% confidence interval were extracted and pooled by using a random-effect model. A significant P-value <0.05 was adopted. Results Six studies with 11 029 patients (4995 with UCS, 4634 with SC, 1346 with CCC and 54 with either SC or CCC) were included. UCS showed a significantly worse prognosis than SC/CCC both overall (HR = 1.51; P = 0.008) and at early stage (HR = 1.58; P < 0.001). Similar results were found for UCS vs SC (HR = 1.53; P < 0.001) and UCS vs CCC (HR = 1.60; P < 0.001). Conclusions Compared to SC and CCC, UCS has a significantly worse prognosis, with a 1.5-1.6-fold increased risk of death. This might justify a more aggressive treatment for UCS compared to SC and CCC. Further studies are necessary to define the prognostic impact of different molecular subgroups.