Long-term results of intraoperative electron beam radiotherapy for primary and recurrent retroperitoneal soft tissue sarcoma

Abstract

Purpose: This study assesses the long-term outcome of patients with retroperitoneal sarcoma treated by preoperative external beam radiotherapy, resection, and intraoperative electron beam radiation (IOERT). Methods and Materials: From 1980 to 1996, 37 patients were treated with curative intent for primary or recurrent retroperitoneal soft tissue sarcoma. All patients underwent external beam radiotherapy with a median dose of 45 Gy. This was followed by laparotomy, resection, and IOERT, if feasible. Twenty patients received 10–20 Gy of IOERT with 9–15 MeV electrons. These patients were compared to a group of 17 patients receiving preoperative irradiation without IOERT. Results: The 5-yr actuarial overall survival (OS), disease-free survival, local control (LC), and freedom from distant disease of all 37 patients was 50%, 38%, 59%, and 54%, respectively. After preoperative irradiation, 29 patients (78%) underwent gross total resection. For 16 patients undergoing gross total resection and IOERT, OS and LC were 74% and 83%, respectively. In contrast, these results were less satisfactory for 13 patients undergoing gross total resection without IOERT. For these patients, OS and LC were 30% and 61%, respectively. Four patients experienced treatment-related morbidity. Conclusions: In selected patients, IOERT results in excellent local control and disease-free survival with acceptable morbidity.