Clinical significance of margin status in postoperative radiotherapy for extremity and truncal soft-tissue sarcoma.

Purpose: To evaluate whether adjuvant radiotherapy (RT) in extremity and truncal soft-tissue sarcoma (STS) patients with microscopically positive or close margins after excision can achieve comparable local control to that of excision with negative margin plus RT.

Methods And Materials: A total of 150 patients (111 extremity and 39 trunk cases) treated with conserving surgery and adjuvant RT was analyzed. All surgical margins were classified as being a negative margin or a positive or close margin based on pathologic margin width. RT was delivered with a shrinking-field technique in 150 patients (median, 63 Gy).

Results: All patients were divided into two groups: (A) excision with negative margins plus RT (n = 56) and (B) excision with positive or close margins plus RT (n = 94). Overall, the 5-year local failure-free survival in all patients was 72.9%, and no significant differences were found between the two groups (Group A, 74.7%; Group B, 71.6%). High tumor grade was found to be a significant predictor of local failure. However, Group A was superior to Group B in distant metastasis-free survival (p = 0.02). No significant differences were shown in overall survival between the two groups.

Conclusions: In our series, margin status did not predict for LF when adjuvant RT was used. We believe that when adjuvant RT is used, re-resection may not be necessary for selected patients with positive or close pathologic margins in the management of extremity and truncal STS patients.