High-dose-rate postoperative vaginal cuff irradiation alone for stage IB and IC endometrial cancer

To evaluate the effectiveness of postoperative high-dose-rate (HDR) vaginal cuff irradiation alone (1500 cGy in 3 fractions) in patients with Stage Ib and Ic endometrial cancer.

This is a retrospective review of 102 patients with Stage Ib and Ic endometrial cancer treated with a hysterectomy and postoperative HDR intracavitary therapy alone during the period of 1/1/90-12/31/96. Each patient received 1500 cGy in 3 weekly treatments, dosed to a depth of 0.5 cm. Pathologic features such as depth of invasion, tumor grade, lower uterine segment (LUS) involvement, and lymphvascular invasion (LVI) were evaluated for their impact on recommended postoperative treatment. All survival curves were generated utilizing Kaplan-Meier methods and all statistical comparisons were via a Wilcoxon rank sum test.

The 5-year actuarial overall survival (OS) is 84% and the 5-year disease-free survival (DFS) is 93%. Locoregional disease control (pelvic control) was excellent with 97% of the patients free of pelvic disease at 5 years. Of the three pelvic failures only one was in the vaginal cuff. LVI, LUS involvement, Grade 3 and/or outer third myometrial involvement were identified in 41 patients. Thirty-one of these patients underwent a lymphadenectomy and there were two regional failures within this increased-risk group.

We obtained an excellent level of locoregional control with minimal morbidity and minimal time commitment for treatment with vaginal HDR brachytherapy alone. Our dose per fraction and total dose is lower than most reported series and there is no apparent loss in locoregional control. In addition, intermediate-risk patients and patients with an increased risk of recurrence (Grade 3, outer third myometrial involvement, LVI, LUS) may be treated with cuff irradiation alone, after surgical staging and a negative lymphadenectomy.