A nomogram-based overall survival stratification to identify uterine sarcoma patients without distant metastases who may benefit from adjuvant radiotherapy.

Objective: Adjuvant radiotherapy has been commonly performed in uterine sarcoma patients, but its role in overall survival (OS) remains controversial. Therefore, our study aimed to build a nomogram-based prognostic stratification to identify uterine sarcoma patients who might benefit from adjuvant radiotherapy.

Methods: Uterine sarcoma patients without distant metastases between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The LASSO Cox regression was performed to identify essential prognostic predictors and a nomogram was built to predict the 1-, 3-, and 5-year OS. Receiver operating characteristic (ROC), calibration curves, and decision curve analysis (DCA) were used to validate the nomogram. Finally, prognostic stratification was performed by decision tree analysis based on the total points of the nomogram.

Results: 2871 patients with uterine sarcoma were included. Preliminary analysis suggested that adjuvant radiotherapy failed to provide an OS benefit for the total population without our nomogram. The built nomogram showed good discrimination and calibration abilities to predict the OS in uterine sarcoma patients and the patients were stratified into three risk groups based on the nomogram. For patients in the high-risk group, adjuvant radiotherapy significantly improved the 5-year OS and median survival time by 26.4% and 17 months, respectively (P < 0.001); while radiotherapy failed to improve the survival outcomes of patients in the low- and intermediate-risk groups.

Conclusions: The nomogram-based prognostic stratification provides preliminary characterization of uterine sarcoma patients who may benefit from radiotherapy. The newly defined high-risk patients may gain significant OS benefit from adjuvant radiotherapy.