Intensity modulated radiation therapy for definitive treatment of paraortic relapse in patients with endometrial cancer.

Abstract: Purpose: The paraortic nodes are a common site of recurrence of endometrial cancer, especially among patients previously treated with pelvic radiation. Intensity modulated radiation therapy (IMRT) can be used to deliver a tumoricidal dose to paraortic disease while minimizing dose to normal adjacent structures. In this study, we reviewed the outcomes of patients treated with IMRT for unresected or incompletely resected paraortic recurrences of primary uterine cancer. Methods and Materials: Between 2000 and 2009, 27 patients with unresected (19 patients) or incompletely resected (8 patients) paraortic relapse of endometrial cancer were treated with curative intent using IMRT. The paraortic basin was generally treated to a dose of 45-50 Gy, and gross disease was treated to a mean total dose of 61.7 Gy (range, 54-66 Gy). Seventeen patients (63%) received neoadjuvant or adjuvant chemotherapy. Fifteen (56%) received cisplatin concurrently with IMRT. Rates of overall survival and progression-free survival following salvage IMRT were determined using the Kaplan-Meier method, and differences between subgroups were assessed using the log-rank statistic. Results: Of the 27 patients, 19 (70%) had local control of paraortic disease after a median follow-up time of 25 months (range, 4-83 months). Two-year actuarial overall survival and progression-free survival rates were 63% and 53%, respectively. Five patients (19%) experienced severe late gastrointestinal toxic effects (grade 3-5). Conclusions: IMRT can serve as salvage therapy of paraortic recurrence of endometrial cancer. However, the risk of severe gastrointestinal toxic effects is high, and care should be taken during treatment planning to minimize the dose to the small bowel. [Copyright &y& Elsevier]