Partial Length Vaginal Brachytherapy for Endometrial Carcinoma with High-Risk Features is As Effective As Full Length with Reduced Toxicity

Purpose: Full-length vaginal (FLV) brachytherapy for patients with endometrial cancer and high-risk features should be considered as per the American Brachytherapy Society to reduce distal vaginal recurrence in patients with endometrial cancers with papillary serous/clear cell histologies, grade 3 status, or extensive lymphovascular invasion. We sought to investigate this patient population and report outcomes of treatment with high-dose-rate (HDR) brachytherapy in women treated with FLV brachytherapy versus partial-length vaginal (PLV) brachytherapy. Methods and materials: With institutional review board approval, we identified patients with endometrial cancer meeting American Brachytherapy Society criteria of high-risk features treated with adjuvant HDR between 2004 and 2010. HDR doses were 21Gy in 3 fractions delivered to either the full-length or partial-length vagina. Acute and late toxicities were evaluated using the Radiation Therapy Oncology Group scale and Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer grading, respectfully. Vaginal recurrences were assessed by physical examination and pap smears. Statistical analyses were performed using SPSS version 23 software. Results: Of 240 patients treated with HDR brachytherapy, 121 were treated with FLV brachytherapy, and 119, with PLV brachytherapy. The median follow-up was 9.5 years (range, 8-11 years) for FLV patients and 8.5 years (range, 7-10 years) for PLV patients; 0% of patients had vaginal recurrences, and 1.4% and 0.9% had proximal vaginal recurrences, respectively (P = .54). All patients treated with FLV brachytherapy developed grade 3 mucositis of the lower vagina/introitus (P < .0001) and had increased analgesics use compared with those treated with PLV brachytherapy (P < .0001). In total, 23% of patients treated with FLV brachytherapy developed grade 3 stenosis of the lower vagina/introitus, in contrast to 0% of patients treated with PLV brachytherapy (P < .0001). Conclusions: PLV brachytherapy is as effective as FLV brachytherapy in reducing local recurrence and causes a significantly lower incidence of acute and late toxicities. The results of this study caution radiation oncologists regarding the careful use of FLV brachytherapy in patients with endometrial cancer and high-risk features. Copyright (C) 2023 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.