Supplementary Material for: Clinical Value of clip-and-snare assisted endoscopic submucosal resection in Treatment of Rectal Neuroendocrine Tumors

Introduction: To introduce a new endoscopic technology, clip-and-snare assisted endoscopic submucosal resection (CS-ESMR) for treatment of rectal neuroendocrine tumors (NETs), and then to investigate the therapeutic value of CS-ESMR. Methods: In this retrospective study, 67 patients who underwent endoscopic treatment of rectal NETs from March 2017 to Dec 2021 were analyzed. According to the endoscopic resection methods (EMR, CS-ESMR and endoscopic submucosal dissection (ESD)), the cases were divided into CS-ESMR group (27 cases), ESD group (31 cases), and EMR group (9 cases). The pathological R0 resection rate and the incidence of adverse events (bleeding and perforation) were compared among the three groups. Results: There was a significant difference about the pathological R0 resection between the CS-ESMR group and the EMR group and between the CS-ESMR group and the ESD group(both P<0.05); Compared with ESD group, the procedure time, intraoperative bleeding and the cost of CS-ESMR group are significantly decreased (P<0.001, P<0.05, P<0.001, respectively). Conclusion: CS-ESMR may be a safe and effective treatment for rectal NETs with a diameter of less than 10mm, without muscularis propria invasion and metastasis.