Stereotactic ablative radiation therapy for pulmonary metastases from sarcoma primaries: A systematic review and meta-analysis of safety and efficacy

Background: Though promising retrospective and prospective studies have reported on stereotactic ablative radiation therapy(SABR) for management of lung metastases from sarcoma primaries, they are limited by small patient numbers. Methods: The primary outcomes of interest were 1-year and 2-year local control (LC) and Grade 3-5 toxicities. Secondary outcomes were 1-year overall survival (OS) and 2-year OS. Weighted random effects meta-analyses using the DerSimonian and Laird methods were performed to calculate effect sizes. Results: Thirteen studies were identified with 533 patients and 940 lung metastases. The median prescription dose was 50 Gy (range: 48-60 Gy) in 5 fractions (range: 4-10). Following SABR, 1- and 2-year pooled LC rates were 97% (95% CI: 95-98%) and 91% (95% CI: 88-95%), respectively. Pooled 1- and 2-year OS rates were 85% (95% CI: 80-90%) and 68% (95% CI: 57-80%), respectively. The estimated incidence of Grade 3-5 toxicities following SABR was 0.1% (95% CI: 0-0.5%). Conclusion: SABR for sarcoma pulmonary metastases resulted in excellent LC with minimal toxicities.