Background: Uterine sarcoma is a group of rare gynecologic tumors with various natures, and different lines of treatment. Most have a poor treatment outcome. This study targeted clinical characteristics, treatment, overall survival (OS), progression-free survival (PFS), and prognostic factors in uterine sarcoma patients in one tertiary center for cancer care. Materials and Methods: Uterine sarcoma patients who were treated at the Department of Obstetrics and Gynecology, Faculty of Medicine Vajira Hospital between January 1994 and December 2014 were identified. Clinico-pathological data were analyzed. Prognostic outcomes were examined by Kaplan-Meier curves and Cox regression analysis. Results: We identified 46 uterine sarcoma patients: 25 carcinosarcoma (CS) (54.3%), 15 leiomyosarcoma (LMS) (32.6%), and 6 undifferentiated uterine sarcoma (UUS) (13.1%) cases. Mean age was 54.0±11.9 years (range 25-82 years). Abnormal uterine bleeding was the most common presenting symptom (63.0%). Among 33 patients (71.7%) who had pre-operative tissue collected, diagnosis of malignancy was correct in 29 (87.9%). All patients received primary surgery and retroperitoneal lymph nodes were resected in 34 (73.9%). After surgery, 5 (10.9%) had gross residual tumors. Stage I disease was most commonly found (56.5%). Adjuvant treatment was given to 27 (58.7%), most commonly chemotherapy. After a median follow-up of 16.0 months (range 0.8-187.4 months), recurrence was encountered in 22 patients (47.8%). Median time to recurrence was 5.8 months (range1.0-105.5 months). Distant metastasis was more common than local or locoregional failure. The 2-year PFS was 45.2% (95% confidence interval [CI], 30.6%-59.7%) and the 2-year OS was 48.3% (95% CI, 33.3%-60.7%). Multivariable analyses found residual disease after surgery as a significant factor only for PFS. Conclusions: Uterine sarcoma is a rare tumor entity. Even with multimodalities of treatment, the prognosis is still poor. Successful cytoreductive surgery is a key factor for a good survival outcome.Keywords: Uterine sarcoma -clinical characteristics -survival -prognostic factors -Thailand RESEARCH ARTICLE Uterine Sarcoma: Clinical Presentation, Treatment and Survival Outcomes in ThailandChalermrat Potikul, Siriwan Tangjitgamol*, Jakkapan Khunnarong, Sunamchok Srijaipracharoen, Thaovalai Thavaramara, Kamol Pataradool the mainstay of treatment (Prat, 2009). Slightly different from its carcinoma counterpart, ovarian preservation and exemption of lymph node resection are sometimes acceptable particular in younger age patients and in those with certain types of sarcoma (Leitao et al., 2003;Kapp et al., 2008). Adjuvant therapy after surgery has evolved over the years without a clear benefit on survival (Cearbhail and Hensley, 2010;Rauh-Hain and Carmen, 2013;Cantrell et al., 2015).Despite being derived from various cellular origins and having different pathologic features, most sarcomas have aggressive behavior, high rates of recurrence and poor prognosis even when diagnosed at an early st...