LIMB-PRESERVING TREATMENT FOR SOFT-TISSUE SARCOMAS OF THE EXTREMITIES- THE SIGNIFICANCE OF SURGICAL MARGINS

Background and Methods. Between 1970 and 1990, 74 patients with extrem ity soft tissue sarcomas began a regimen of limb-sparing surgery and i rradiation. Ninety-two percent received postoperative irradiation, 7% received preoperative irradiation, and one patient was treated with ra diation after an incisional biopsy only. Radiation was administered wi th a shrinking-field technique (median total dose, 63 Gy; range, 39.6- 71 Gy), with 14 patients receiving interstitial brachytherapy as a com ponent of treatment. Ten patients received adjuvant chemotherapy. Resu lts. Local control of disease was 82% at 5 years, and 95% after salvag e therapy. The actuarial risk of distant disease recurrence was 27%, w ith an overall survival rate of 70% at 5 years. Histologic subtype, tu mor grade, size of tumor, location of tumor, status of the surgical ma rgins, use of chemotherapy, radiation dose, interval until initiation of radiation therapy, and use of a brachytherapy boost were analyzed t o determine their effect on survival, local control, and freedom from distant metastasis. Microscopic involvement of the surgical margins pr edicted for local disease recurrence (P = 0.0002), distant disease rec urrence (P = 0.008), and poorer overall survival (P = 0.02). Low histo logic grade was favorably correlated with freedom from distant disease recurrence (P = 0.004) and survival (P = 0.002). Patients with liposa rcomas had superior local control (P = 0.004) compared with patients w ith tumors of other histologic subtypes. Five patients experienced a c omplication of therapy, for an actuarial risk of 10% at 5 years. Only two patients required hospital admittance for treatment-related morbid ity. Conclusions. These findings support the continued use of limb-pre serving management for extremity sarcomas and emphasize the importance of the status of the surgical margins.