External Beam Radiation Therapy for Resectable Soft Tissue Sarcoma: A Systematic Review and Meta-Analysis

The aim of this study was to evaluate the role of preoperative and postoperative external beam radiation therapy (EBRT) in the treatment of resectable soft tissue sarcomas (STSs) of different tumor locations. A systematic literature search was performed to identify studies investigating the effects of EBRT (versus no EBRT) on local recurrence (LR) and overall survival (OS) or comparing different EBRT sequences. Random effects meta-analyses were calculated and presented as cumulative odds ratios (ORs). Sixteen studies (n = 3958 patients) comparing EBRT versus no EBRT, including one randomized controlled trial (RCT) in extremity sarcoma, were analyzed. EBRT appeared to reduce LR in both retroperitoneal tumors (OR 0.47, p < 0.0001) and other locations (OR 0.49, p = 0.001). OS was improved by EBRT in retroperitoneal STSs (OR 0.37, p < 0.0001) but not in other tumor locations. Eleven studies (n = 2140), including one RCT, compared preoperative and postoperative radiotherapy. LR was less frequent following preoperative EBRT in retroperitoneal STSs (OR 0.03, p = 0.02), as well as in other tumor locations (OR 0.67, p = 0.01), while wound complications in extremity sarcoma were more frequent following preoperative EBRT (OR 2.92, p < 0.0001). Several studies included in this meta-analysis bear a high risk of bias and no RCT has been published for retroperitoneal STS. This meta-analysis supports the use of EBRT for local tumor control in patients with resectable STSs. Based on a small number of non-randomized studies, a positive effect on OS may exist in the subgroup of retroperitoneal STSs.