Treatment of cervical/vaginal intra-epithelial neoplasia with high-dose-rate brachytherapy: a multi-center retrospective analysis

Abstract

Objective: Cervical intra-epithelial neoplasia and vaginal intra-epithelial neoplasia are pre-cancerous lesions of the uterine cervix and vagina, for which various treatment modalities have been proposed. This study aimed to evaluate the efficacy and safety of high-dose-rate intra-cavitary brachytherapy in the treatment of cervical/vaginal intraepithelial neoplasia. Methods: This multi-center retrospective study reviewed patients with cervical/ vaginal intra-epithelial neoplasia from January 2012 to December 2022. All patients received high-dose-rate intra-cavitary brachytherapy with radical or salvage intent. Treatment outcomes were estimated using Kaplan-Meier analysis. Results: A total of 76 patients with cervical intra-epithelial neoplasia (n = 27) or vaginal intra-epithelial neoplasia (n = 49) were analyzed. Among the total patients, 24 had received previous radiation therapy, including external beam radiation therapy (n = 23), brachytherapy (n = 13), or both. The most common regimen delivered 30 to 35 Gy in 5 to 6 fractions (60.5%), followed by 40 Gy in 8 fractions (21.1%), at a median prescription point of 5 mm (range; 0-7.5). The median follow-up period was 30.1 months (range; 0.5-124.7). Ten patients received high-dose-rate intra-cavitary brachytherapy as the first treatment for newly diagnosed cervical/vaginal intra-epithelial neoplasia (de novo). Thirty-two patients (42.1%) had a cervical/vaginal intra-epithelial neoplasia recurrence after invasive cervical/vaginal cancer, and 34 patients (44.7%) were treated for persistent cervical/vaginal intra-epithelial neoplasia. The 3-year local control rate was 89.3% and the 3-year progression-free survival rate was 85.0%. Notably, the 10 de novo patients had a 100% local control rate. Acute grade 1/2 urinary toxicity was the most common adverse effect (n = 9, 11.8%). Grade 3 late toxicity occurred in only 1 patient who had previously received brachytherapy. Conclusions: High-dose-rate intra-cavitary brachytherapy demonstrated excellent local control with tolerable adverse effects for the treatment of cervical/vaginal intraepithelial neoplasia. These findings may support the potential of brachytherapy as a viable treatment option for cervical/vaginal intra-epithelial neoplasia.