Phase I Trial of Preoperative Concurrent Doxorubicin and Radiation Therapy, Surgical Resection, and Intraoperative Electron-Beam Radiation Therapy for Patients With Localized Retroperitoneal Sarcoma

Abstract

The primary objective of this phase I trial was to define the maximum-tolerated dose of external-beam radiation with concurrent fixed-dose continuous-infusion doxorubicin followed by surgical resection and electron-beam intraoperative radiation therapy (EB-IORT) for patients with localized, potentially resectable retroperitoneal sarcomas (RPS). Thirty-five patients with radiographically resectable primary or recurrent intermediate- or high-grade RPS were treated. Doxorubicin was administered each week for 4 or 5 weeks as an initial bolus (4 mg/m2) followed by a 4-day continuous infusion (4 mg/m2/d). Concurrent radiation therapy was administered in escalating doses of 18.0, 30.6, 36.0, 41.4, 46.8, or 50.4 Gy in 1.8-Gy fractions. Radiographic restaging was performed 4 to 8 weeks after chemoradiation, and patients with localized disease underwent surgical resection with EB-IORT (15 Gy). Chemoradiation was completed as outpatient therapy in 31 patients (89%); four patients required hospital admission during chemoradiation or in the postchemoradiation preoperative period. At the highest radiation dose of 50.4 Gy, two (18%) of 11 patients had grade 3 or 4 nausea. Twenty-nine patients (83%) underwent laparotomy; six patients had interval disease progression and did not undergo surgery. Grossly complete resection (R0 or R1) was performed in 26 (90%) of 29 patients who had surgery. EB-IORT was feasible and successfully administered to 22 patients who had R0 or R1 resections. Preoperative chemoradiation, surgical resection, and EB-IORT are feasible for patients with RPS. Preoperative external-beam radiation can be administered to a total dose of 50.4 Gy with continuous-infusion doxorubicin.