Clinical Practice Pattern Of Adjuvant Vaginal Brachytherapy In Early-stage Endometrial Carcinoma According To ESMO-ESGO-ESTRO Risk Classification: Long-term updated Data From A Multi-institutional Analysis In China

Abstract

To evaluate the clinical practice pattern of adjuvant vaginal brachytherapy (VBT) in early-stage endometrial carcinoma (EC) according to ESMO-ESGO-ESTRO risk classification in China from long-term updated data of a multi-institutional analysis. We retrospectively evaluated clinical data of patients with early-stage EC at 13 institutions in China between 2000 and 2015. Eligibility requirements included the primary hysterectomy/bilateral salpingo-oophorectomy and adjuvant radiotherapy, stage I and II disease (FIGO 2009 staging), and complete clinicopathologic and follow-up information. All patients were divided into low-risk (LR), intermediate-risk (IR), high-intermediate risk (HIR) and high-risk (HR) groups according to ESMO-ESGO-ESTRO risk classification. We evaluated clinical practice pattern and tendency of VBT in different risk groups during various periods. Proportions were compared by using the Chi square test for values of 5 or higher and with Fisher’s exact test for values of less than 5. All data were examined using statistical analysis software. A total of 1268 early-stage patients were reviewed and 1108 cases with intact data were included in the analysis. The median follow-up time was 53 months (range 6–207 months). The median age was 56 years (range 23–86 years). Stage Ia/b disease represented 86.0% of the cohort, HR patients 22.9%, HIR patients 20.0%, IR patients 29.2%. Patients received VBT alone (43.2%, n = 479), EBRT alone (14.3%, n = 158), EBRT+VBT (42.5%, n = 471), and chemotherapy (22.9%, n = 235). In HR and HIR groups, the proportion of VBT alone increased 33.3% (0 vs. 33.3%) and the proportion of VBT boost after EBRT decreased 10.5% (61.3% vs. 50.8%) from 2000 to 2015. In IR and LR groups, VBT alone increased 61.7% (4.7% vs. 66.4%) and VBT boost decreased 29.4% (51.6% vs. 22.2%) in the corresponding period. All institutions commonly use High-dose-rate(HDR) VBT. The commonly used applicators include the multichannel vaginal cylinder (77.7%), single channel vaginal cylinder (16.7%) and ovoids (5.6%). A fixed 3-4cm length of the proximal vagina was reported by 62.9%, a proximal 1/3-1/2 length of the vagina by 36.2%, and Entire vagina by 0.8%. Specify dose: 77.7% specify to 0.5-cm depth from the vaginal surface, and 22.3% specify elsewhere. There were 11 and 13 different dose-fractionation schedules for VBT alone and VBT boost, respectively. The most common fractionation for VBT alone and VBT boost is 5 Gy for six fractions and 5 Gy for two fractions, both to 0.5-cm depth. Our study provides an assessment of clinical practice pattern for adjuvant VBT management of early-stage EC in China. Historical data demonstrate that the clinical practice of adjuvant VBT alone increased significantly in different risk classification groups over the past 15 years, especially in IR to HR groups.