Re-resection with brachytherapy for locally recurrent soft tissue sarcoma arising in a previously radiated field

PURPOSE The use of further radiotherapy among patients with soft tissue sarcoma tha t recurs in a previously irradiated area is controversial. Presented is a r eview of our 7-year experience with brachytherapy for recurrent soft tissue sarcoma . METHODS A retrospective review was performed of 26 patients who underwent periopera tive brachytherapy between 1990 and 1997 for recurrent soft tissue sarcoma In all cases, the sarcoma recurred within a previously irradiated field Aft er-loading brachytherapy catheters were placed at the time of surgical exti rpation of the sarcoma within a single-plane implant by use of 1-cm interca theter spacing. Insertion of the radioactive Ir-192 wire was delayed until the fifth to seventh postoperative day to allow initial wound healing. The prescribed dose rate for the 192Ir wire ranged be tween 50 and 80 cGy an ho ur, and the dose was specified at 0.5 an from the plane of the implant The anatomic locations treated included lower extremity (N = 10), upper extremi ty (N = 7), trunk (N = 7), and head and neck (N = 2). RESULTS Total tumor extirpation, confirmed by negative frozen section margins, was accomplished in all cases. The mean dose of external-beam irradiation recei ved before brachytherapy was 55.6 Gy +/- 1.8 Gy (range, 30.0 to 70.3 Gy), T he mean dose of radiation prescribed at the implant procedure was 47.2 Gy /- 1.6 Gy (range, 11.0 to 50.0 Gy), A tissue transfer flap was placed over the bed of resection in 13 cases. Complications occurred in five patients i ncluding, three with wound breakdown, one with osteonecrosis, and with neur algia Operative intervention was required in four of the five patients with complications; each of the patients requiring operative intervention for w ound-related complications had undergone primary wound closure without tiss ue transfer. Recurrence of disease occurred in 13 patients: nine local and four distant metastases. The median follow-up was 16 months (range, 2 to 73 months). The 5-year local recurrence-free, distant recurrence-free, diseas e-free, and overall survival rates after brachytherapy were 52%, 75%, 33%, and 52%, respectively. CONCLUSION Re-irradiation of recurrent soft tissue sarcoma by brachytherapy in conjunc tion with resection can be performed with acceptable complication rates. Lo cal control can be achieved for the majority of patients who would otherwis e require more radical surgical procedures.