Purpose of investigation: The objective of this retrospective multicenter study was to assess the prognostic relevance of histolo­gic type in uterine sarcomas. Methods: The hospital reports of 249 patients with uterine sarcomas were reviewed. Surgery was the initial therapy for all patients. Histologic type was leiomyosarcoma in 95 cases, low-grade endometrial stromal sarcoma (ESS) in 19, high-grade ESS in 34, and carcinosarcoma in 101. Postoperative treatment was given without well-defined protocols. Median follow-up of survivors was 97 months. Results: In the whole series 2-year, 5-year, and 10-year survival rates were 53.5%, 41.6%, and 35.8%, respectively, and median survival was 31 months. At univariate analysis survival was significantly related to stage (p = 0.0001), mitotic count (p = 0.0001), and histologic type (low-grade ESS vs leiomyosarcoma vs carcinosarcoma vs high-grade ESS, median: not reached vs 27 months vs 21 months vs 16.5 months, p = 0.0011), but not to postoperative therapy and patient age. The Cox model revealed that tumor stage, mitotic count and histologic type were independent prognostic variables for survival. In detail, the risk of death was signifi­cantly lower for low-grade ESS (risk ratio [RR] = 0.257; 95% confidence interval [Cl] = 0.071-0.931) and carcinosarcoma (RR= 0.509; 95% CI = 0.324-0.799) when compared to leiomyosarcoma. Conversely, no significant difference in survival was found between leiomyosarcoma and high-grade ESS. Conclusions: Histologic type is an independent prognostic variable for survival in uterine sarcomas. Low-grade ESS has the best clinical outcome, whereas leiomyosarcoma has the poorest one. It is noteworthy that, when adjusting for stage and mitotic count, leiomyosarcoma has a significantly worse prognosis than carcinosarcoma.