Background: To examine the role of radiotherapy (RT) in uterine leiomyosarcomas (LMS) and to determine the patient population who may benefit from RT.
Methods: From 1998-2008, 69 patients with primary uterine LMS underwent hysterectomy with or without pelvic radiotherapy to a median dose of 45 Gy. Univariate analysis was performed using the Kaplan-Meier method and cumulative-incidence function, and multivariate analyses using Fine and Gray or Cox proportional hazard models.
Results: Following surgery, 32 out of 69 patients received RT. There was no evidence of any correlation between patient, disease and treatment characteristics and the use of RT. Median follow-up was 57 months. RT was associated with reduced local recurrence (3y LR 19% vs. 39%; Gray's p = 0.019) and improved overall survival (3y OS 69% vs. 35%; log-rank p = 0.025) on univariate analysis. Multivariate analysis demonstrated that RT reduced LR (HR: 0.28, CI: 0.11-0.69, p = 0.006) and increased OS (HR: 0.44, CI: 0.23-0.85, p = 0.014) independent of other clinical and pathologic factors. Positive surgical margins increased the odds of LR (HR: 5.6, CI: 2.3-13.4, p = 0.00012). Large tumor size and advanced stage (II-IV) were associated with the development of distant metastases and inferior OS.
Conclusions: Postoperative pelvic RT reduces LR and improves OS of patients with uterine LMS.