Intraoperative radiation therapy in gynecologic cancer: the Mayo Clinic experience

Nineteen patients with recurrent and two patients with locally advanced gynecologic malignancies received intraoperative radiation therapy (IORT) with electrons at the Mayo Clinic. Fourteen of the patients also received external beam irradiation. Actuarial local control with or without central control at 5 years was 71%, and actuarial control within the IORT field (central control) was 80%. The distant metastases rate at 5 years was 47%. Actuarial 2- and 5-year overall survival was 58 and 33%, respectively, and disease-free survival was 47 and 40%, respectively. Patients with microscopic disease had significantly higher 5-year disease-free and overall survival (70 and 67%, respectively). In summary, IORT in combination with maximum debulking surgery with or without external beam therapy in patients with paraaortic or pelvic sidewall recurrences of gynecologic malignancies appeared to improve long-term local control and survival. The addition of hyperthermia or hypoxic sensitizers may be a consideration to further improve local control in patients with gross residual disease. The high incidence of distant metastasis warrants the search for effective systemic chemotherapy. IORT-related toxicity was acceptable.