Patterns of failure in endometrial carcinoma stage IB grade 3 and IC patients treated with postoperative vaginal vault brachytherapy

Objective. The vagina is the most common site of locoregional failure in surgical stage IB, IC, and II (occult) endometrial adenocarcinoma. The objective of this study is to evaluate the therapeutic efficacy of vaginal vault brachytherapy alone for surgical stage I patients with high-risk features. Materials and methods. The study group consists of high-risk stage I patients with either stage IB grade (G)3 or any grade IC disease. From February 1991 to August 1997, 124 patients with endometrial carcinoma were treated postoperatively with high-dose-rate vaginal vault brachytherapy as the only adjuvant treatment. All patients were surgically staged. Among them, 38 patients were identified as high risk. Twelve patients had stage IBG3, 14 had ICG1, 9 had ICG2, and 3 had ICG3 disease. The median age was 67 years (range 41 to 86 years). A dose of 21 Gy in three fractions of 7 Gy each was delivered to a prescription depth of 0.5 cm from the surface of the vaginal applicator using high-dose-rate brachytherapy. Results. The median follow-up was 30 months (range 7 to 91 months). No patient has developed a vaginal or pelvic recurrence. Three patients developed tumor recurrence in the upper abdomen at 11, 18, and 37 months. Two of the three patients with recurrent disease also had history of breast cancer. In one patient, breast cancer was diagnosed 4.8 years prior and in the second 3 years subsequent to the diagnosis of endometrial cancer. The 5-year actuarial overall survival and disease-free survival are 93 and 87%, respectively. There was no treatment-related grade 3 or 4 morbidity observed. Conclusions. For patients with surgical stage IBG3 and IC, excellent local control and minimal morbidity has been observed with the selective use of vaginal brachytherapy alone. Further studies and longer follow-up are warranted, (C) 1999 Academic Press.