Soft Tissue Sarcomas of the Extremities: Surgical Margins Can Be Close as Long as the Resected Tumor Has No Ink on It.

BACKGROUND Soft tissue sarcomas (STS) arising in the extremities pose a therapeutic challenge due to concerns of functional morbidity. Resections with negative margins are the mainstay of therapy, but the prognostic significance of surgical margins remains controversial. The purpose of this study was to determine the prognostic impact of surgical margins and clear margin widths in patients with STS of the extremities. MATERIALS AND METHODS We assessed the relationship between local recurrence-free (LRFS), disease-specific (DSS), and metastasis-free survival (MFS) and potential prognostic factors retrospectively in a consecutive series of 643 patients treated at our institution between 1996 and 2016. Potential prognostic factors were assessed using univariate and multivariate analyses. RESULTS The median follow-up time after primary diagnosis was 5.4 years (95% confidence interval [CI]: 4.8-6.0). The five-year estimates of the DSS, LRFS, and MFS rates in the entire cohort were 85.3% (95% CI: 81.6-88.3), 65.3% (95% CI: 60.8-69.5) and 78.0% (95% CI: 74.1-81.4), respectively. Histological grade and the quality of surgical margins were independent prognostic factors of all three survival endpoints (LRFS, DSS, MFS) in multivariate analyses. Within the R0 subgroup, univariate and multivariate analyses of categorized (≤1 mm vs. 1-5 mm vs. >5 mm) and non-categorized margin widths revealed that close and wide negative margins led to similar outcomes. Adjuvant radiation improved local control independently, but not DSS and MFS. CONCLUSION Microscopically negative margins were associated with better LRFS, DSS, and MFS regardless of whether adjuvant radiation was applied. Here, surgical margins can be close as long as the resected tumor has no ink on it. IMPLICATIONS FOR PRACTICE In the present retrospective analysis of 643 patients with primary soft issue sarcomas of the extremities, surgical margins could be identified as independent predictors of local recurrence-free, disease-specific, and metastasis-free survival. Given the diminished outcome of patients left with positive margins, surgical efforts should aim to achieve microscopically negative margins whenever feasible. It is noteworthy that only the quality of surgical margins, but not the negative margin width attained, had an influence on the prognosis. Our findings suggest that surgical margins can be close as long as the resected tumor has no ink on it.