Impact of resection margin on outcomes in high-grade soft tissue sarcomas of the extremity-A USSC analysis

The optimal margin of resection for high-grade extremity sarcomas and its impact on survival has long been questioned in the setting of adjuvant radiotherapy. The objective of this study was to investigate the impact of resection status on recurrence and survival.

All patients with primary, nonmetastatic, high-grade extremity sarcomas that underwent surgical resection from January 2000 to April 2016 in the U.S. Sarcoma Collaborative (USSC) were retrospectively reviewed. Recurrence patterns, recurrence-free survival (RFS), and overall survival (OS) were examined in multivariate analyses (MVA).

A cohort of 959 patients was identified with a median follow-up of 34.7 months from diagnosis. R0 resection was achieved in 86.7% (831) while R1 resection in 13.3% (128). Locoregional recurrence for R0 and R1 groups occurred in 9.1% (76) versus 14.8% (19; p = .05) while distant recurrence occurred in 24.7% (205) versus 26.6% (34; p = .65), respectively. Median RFS was 171.2 versus 48.5 (p = .01) while median OS was 149.8 versus 71.5 months (p = .02) for the R0 versus R1 group, respectively. On MVA, female gender (hazard ratio [HR] = 0.69, p = .007) and adjuvant radiotherapy (0.7, p = .04) were associated with improved OS, whereas older age (HR = 1.03, p < .001) and tumor size (HR = 1.01, p < .001) were associated with worse OS. R0 resection status was associated with improved locoregional RFS (HR = 0.56, p = .03) but not with distant RFS (HR = 0.84, p = .4) or OS (HR = 0.7, p = .052).

In high-grade extremity sarcomas, tumor size and gender are predictive of OS while R0 resection status is associated with improved locoregional recurrence rate without a significant impact on distant RFS or OS.