A snare combined with endoclips to assist in endoscopic submucosal dissection for intraepithelial neoplasia in the entire colon and rectum

<b>Objective:</b> The use of mucosal traction to assist in colonic and rectal endoscopic submucosal dissection (ESD), especially for deep colonic ESD, is challenging. We developed a method of inverse insertion of a snare into the endoscopic working channel to deliver it into the colon together with the endoscope. With this method, two types of mucosal traction, per-anal external traction (PET) and per-anal internal traction (PIT), could be achieved using a snare with endoclips to assist in ESD (ESD-SE). Here, we aimed to examine its safety and feasibility. <b>Methods:</b> From January 2017 to September 2018, 50 colonic and rectal intraepithelial neoplasias in 50 patients were treated with ESD-SE. Data on lesion location and size, operation time, en bloc resection and R0 resection rates, and operative complications were collected. <b>Results:</b> Among 50 lesions, 15 lesions were located in the deep colon/proximal colon, and 35 lesions were in the distal colon. The median (interquartile range) size of lesions, submucosal dissection time, and total operation time were 4.5 (3.0–5.0) cm, 32 (18–81) min, and 50 (33–108) min, respectively. All lesions were completely resected, with R0 resection rates of 100%. No intraoperative and postoperative complications occurred. Postoperative pathology revealed 40 and 10 cases of high-grade and low-grade intraepithelial neoplasia, respectively. <b>Conclusions:</b> The approach using insertion of a selective snare into the colon together with the endoscope, especially into the deep colon, was safe and simple. Use of the snare combined with endoclips could effectively assist in total colonic ESD. Further research is warranted.

<b>研究目的：</b>采用黏膜牵引辅助结直肠内镜黏膜下剥离术（endoscopic submucosal dissection, ESD），尤其是结肠深部ESD，颇具挑战性。本研究团队研发了一种将圈套器反向插入内镜工作通道的方法，可使其随内镜一同送入结肠腔内。借助该方法，可联合使用圈套器与金属夹实现两种黏膜牵引模式：经肛外部牵引（per-anal external traction, PET）与经肛内部牵引（per-anal internal traction, PIT），以此辅助ESD操作（下称ESD-SE）。本研究旨在评估该方法的安全性与可行性。
<b>研究方法：</b>2017年1月至2018年9月，共纳入50例结直肠上皮内瘤变患者（共50枚病灶），均采用ESD-SE方案进行治疗。收集病灶位置、大小、手术时长、整块切除率、R0切除率及手术并发症相关数据。
<b>研究结果：</b>50枚病灶中，15枚位于结肠深部/近段结肠，35枚位于远段结肠。病灶中位（四分位间距）大小为4.5（3.0~5.0）cm，黏膜下剥离时长中位数为32（18~81）min，总手术时长中位数为50（33~108）min。所有病灶均实现完整切除，R0切除率达100%。未发生术中及术后并发症。术后病理结果显示，高级别上皮内瘤变40例，低级别上皮内瘤变10例。
<b>研究结论：</b>将专用圈套器随内镜一同送入结肠（尤其是结肠深部）的操作方法安全简便。联合使用圈套器与金属夹可有效辅助全结肠ESD操作。仍需开展进一步研究加以验证。