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

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.

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).

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.

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.