Multinational retrospective study of early recurrence and prognosis in patients undergoing resection of primary retroperitoneal sarcoma

Complete surgical resection of retroperitoneal sarcomas (RPS) is the cornerstone of potentially curative treatment; however, recurrence is common and timing of relapse is thought to reflect tumor biology. A retrospective study two high-volume centers in Milan (Italy) and Toronto (Canada) investigated the impact of early recurrence on prognosis in patients undergoing resection of RPS. The study included 651 patients, of whom 566 (87%) underwent resection and 85 (13%) did not. Median follow-up time fron diagnosis was 75.9 months (IQR 58.6-99.5). Among 566 patients undergoing resection, 259 (46%) developed recurrence, including 49 (19%) within 6 months. Patients with disease-free interval (DFI) 0-6 months had similar overall survival (OS) to that of unresected patients (2-year OS 51.6% versus 42.7%; p=0.32), while later recurrence was associated with improved OS (p<0.001). No preoperative clinical variable reliably predicted early recurrence. The authors conclude that improved tools are needed to guide preoperative patient selection and optimize treatment strategies for RPS.