Status of surgical margins and prognosis in adult soft tissue sarcomas of the extremities: a series of patients treated at a single institution.

PURPOSE: To explore the prognostic effect of microscopic marginal status after surgery for extremity soft tissue sarcomas. PATIENTS AND METHODS: We analyzed 911 consecutive patients surgically treated throughout a 20-year span at a single referral center. Six hundred forty-two were first seen with a primary tumor, and 269, with a locally recurrent tumor. All patients underwent macroscopically complete resection. Microscopic marginal status was negative (tumor size > 1 mm) in 748 patients and positive (</= 1 mm) in 163 patients. Median follow-up was 107 months.
RESULTS: Patients with primary disease had a lower disease-specific mortality in comparison to those first examined for recurrence (25% v 37%, respectively, at 10 years). Size, malignancy grade, depth, histotype, and local recurrence had a statistically significant prognostic effect at multivariable analysis, while microscopically positive surgical margins had not, though a trend in favor of negative margins was observed. However, an extra risk was observed for patients with positive margins after 3 to 5 years (hazard ratio, 1.8 after 5 years v 0.8 before 5 years). In patients treated for a local recurrence, the prognostic impact of positive margins was higher (hazard ratio, 1.6).
CONCLUSION: Positive surgical margins had a weak adverse prognostic effect, which was more pronounced for those patients escaping an early relapse. This would seem to justify a policy of surgical adequacy in adult soft tissue sarcomas, though clinical decision making in borderline presentations for conservative surgery might be reasonably flexible and shared with the patient. Once a local relapse has occurred, the impact of local treatments seems more critical.