INTRAOPERATIVE RADIATION-THERAPY IN GYNECOLOGIC CANCER - UPDATE OF THE EXPERIENCE AT A SINGLE INSTITUTION

Purpose: To update the Mayo Clinic experience with intraoperative radi ation therapy (IORT) in patients with gynecologic cancer. Methods and Materials: Between January 1983 and June 1991, 39 patients with recurr ent or locally advanced gynecologic malignancies received intraoperati ve radiation therapy with electrons. The anatomical area treated was p elvis (side walls or presacrum) or periaortic nodes or a combination o f both. In addition to intraoperative radiation therapy, 28 patients r eceived external beam irradiation (median dose, 45 Gy; range, 0.9 to 6 5.7 Gy), and 13 received chemotherapy preoperatively. At the time of i ntraoperative radiation therapy and after maximum debulking operation, 23 patients had microscopic residual disease and 16 had gross residua l disease up to 5 cm in thickness. Median follow-up for surviving pati ents was 43.4 months (range, 27.1 to 125.4 months). Results: The 5-yea r actuarial local control with or without central control was 67.4%, a nd the control within the IORT field (central control) was 81%. The ri sk of distant metastases at 5 years was 52% (82% in patients with gros s residual disease and 33% in patients with only microscopic disease p ostoperatively). Actuarial 5-year overall survival and disease-free su rvival was 31.5 and 40.5%, respectively. Patients with microscopic dis ease had 5-year disease-free and overall survival of 55 and 50%, respe ctively. Grade 3 toxicity was directly associated with IORT in six pat ients (15%). Conclusion: Patients with local, regionally recurrent gyn ecologic cancer may benefit from maximal surgical debulking and IORT w ith or without external beam irradiation, especially those with micros copic residual disease. (C) 1997 Elsevier Science Inc.