Endoscopic Mucosal Resection Using Band Ligation (EBL) Will Serve Two Ends in the Treatment for Small Rectal Neuroendocrine Tumors? A Multicenter Retrospective Study

Abstract

Background: Rectal neuroendocrine tumor (NET)s that are <10mm in diameter can be treated with local excision including endoscopic resection. Endoscopic mucosal resection (EMR) of rectal NETis often associated with involvement of the resection margin. Endoscopic submucosal dissection (ESD) has more histologically complete resection. However, ESD can lead to more serious complications and longer procedure time than EMR.Endoscopic mucosal resection using band ligation (EBL) is a new technique for eliminating the rectal NET. The aim of the this study is to evaluate the therapeutic efficacy and convenience of EBL with that of EMR or ESD for the endoscopic therapy of rectal NET. Methods: From March 2013 to February 2018, we enrolled consecutive patients with rectal NETs less than 15mm in diameter and without lymph node enlargement. The histologic complete resection rate, length of procedures, and post-procedure complications were retrospectively analyzed. Results: Twelve NETs were excised by EBL, and 43 lesions were removed by EMR and 20 lesions were resected using ESD.The histologic complete resection rate was 66.7% in the EBL group, 74.4% in the EMR group, and 90.0% in the ESD group (P=0.249)). The tumor-free deep and lateral resection margins of EBL group were greater than in the EMR group (P< 0.001 and P = 0.093, respectively). There was no perforation in any group.Post-procedure bleeding occurred in three cases of EBL and was controlled endoscopically. Additionaly, the mean procedure time was significantly longer in ESDthan EBL (p<0.001). During the follow-up period, two local recurrence and two distant metastasis were detected in the EMR group only. Conclusions: Compared to EMR, EBL showedsimilar procedure time and complication rate, lower recurrence rate, lower lymphatic invasion, and deeper tumor free resection margin. EBL is technically easy to perform and can be safely performed in less time than ESD.EBL enables deep vertical resection margins and high complete resection ratecomparable to ESD. Considering the benefits of ease, efficiency, and short procedure time, EBL could be considered either an alternative to ESDor an optional therapy for small rectal NET.