Stereotactic Body Radiotherapy for Metastatic and Recurrent Soft Tissue Sarcoma

Abstract BackgroundSoft tissue sarcoma（STS） is a malignant tumor of highly heterogeneous mesenchymal origin. STS has a biologic pattern and clinical transformation with localized invasive growth and susceptibility to hematogenous metastasis. Metastatic and recurrent soft tissue sarcoma may be treated by local therapeutic options, including surgery and radiation therapy. This study evaluated the safety and efficacy of SBRT for metastatic and recurrent soft tissue sarcoma.MethodsWe performed a retrospective analysis of 37 STS patients with 58 lesions treated with SBRT from 2009-2019 at our institution. We analyze the local control (LC), overall survival (OS), progression free survival (PFS) and toxicity rates of the patients.ResultThe median follow-up was 20 months（range 2 to 120 months）. One and two year LC rates were 75.3% and 55.2% [95% confidence interval (CI) 20–25 months]. Median OS was 24 months and the survival rates were 66.6%, 45% and 26.6% at 1, 2 and 3-year after SBRT. Median PFS were 11months (95% CI 8–18 months). No acute or chronic grade ≥ 3 toxicity was observed.ConclusionsIn patients with metastatic and recurrent STS, LC, OS and PFS were higher than expected. SBRT should be a proper treatment option for STS.