Preoperative Radiotherapy and Postoperative Complications Among Patients with Primary Retroperitoneal Sarcoma: A Post Hoc Analysis of the EORTC-62092 (STRASS) Phase 3 Randomized Clinical Trial.

Abstract

To assess the association between preoperative radiotherapy (RT) and major postoperative complications in patients with primary retroperitoneal sarcoma (RPS). The effect of preoperative RT on postoperative morbidity in patients undergoing surgery for primary RPS remains uncertain. In the post hoc analysis, analyses were performed for the entire STRASS cohort and for the subgroup with well-differentiated liposarcoma (WDLPS) and grade 1-2 (G1-G2) dedifferentiated liposarcoma (DDLPS). The exploratory endpoint was the occurrence of major postoperative complications (Clavien-Dindo grade ≥3) within 60 days of surgery, evaluated according to the treatment arm (surgery alone or preoperative RT followed by surgery). Logistic regression models were used to identify whether treatment arm was independently associated with major postoperative complications. A total of 242 patients (124 [51.2%] male; median age, 61 years [IQR, 52-68]) were included. Overall, 128 patients were randomized to surgery alone and 114 to preoperative RT plus surgery. In the WDLPS/G1-G2 DDLPS subgroup (n=122), 59 underwent surgery alone and 63 received preoperative RT. The overall incidence of major postoperative complications was 19.8%, with no significant difference between treatment arms (19.5% surgery alone vs 20.2% preoperative RT; P = 0.90). On multivariable analysis, preoperative RT was not associated with increased odds of major postoperative complications (OR, 0.95; 95% CI, 0.48-1.87; P = 0.88). Findings were consistent in the WDLPS/G1-G2 DDLPS subgroup (OR, 1.57; 95% CI, 0.56-4.41; P = 0.39). These data suggest that concerns regarding postoperative complications should not preclude the use of preoperative RT when clinically indicated.