A PROSPECTIVE RANDOMIZED TRIAL OF ADJUVANT BRACHYTHERAPY IN THE MANAGEMENT OF LOW-GRADE SOFT-TISSUE SARCOMAS OF THE EXTREMITY AND SUPERFICIAL TRUNK

Purpose: This study was designed to evaluate the impact of adjuvant brachytherapy (BRT) on local and systemic recurrence rates in patients with low-grade sarcoma. Patients and Methods: Forty-five patients with histologic low-grade, completely resected soft tissue sarcomas of the extremity or superficial trunk were entered onto this trial. Following resection of all gross disease, patients were randomized to the BRT arm (n = 22) or to the no- BRT arm (n = 23). On the fifth or sixth postoperative day, catheters were loaded with iridium 192 to deliver a dose of 45 Gy to the tumor bed over 4 to 6 days. Results: The two groups were evenly distributed with respect to the distribution of presentation status (primary v recurrent), tumor site (trunk v extremity, proximal v distal extremity), tumor size (< 5 cm v ≥ 5 cm), tumor depth (superficial v deep), and microscopic tumor margins (positive v negative). The predominant histopathologic diagnosis in each group was liposarcoma (BRT, 13 of 22 [59%]; no BRT, 14 of 23 [61%]) with other histopathologic subtypes evenly distributed between the two groups. The median follow-up duration among the ongoing survivors is 67 months. One patient in the BRT group developed systemic disease and died of progressive disease. Local recurrence occurred in five of 23 patients (22%) in the no- BRT group and six of 22 patients (27%) in the BRT group (P = .60). Conclusion: Adjuvant radiation in the form of BRT does not appear to decrease local recurrence rates following complete resection of low-grade extremity and superficial trunk soft tissue sarcomas. Other adjuvant approaches, such as external-beam radiotherapy, are required to have a significant impact on local recurrence rates in this group of patients.