Therapeutic efficacy evaluation of the injection mucosa knife in endoscopic submucosal dissection for rectal neuroendocrine tumors

Background: Endoscopic submucosal dissection (ESD) is preferred for rectal neuroendocrine tumors (NETs), yet technical refinements are needed. This study aims to analyze the therapeutic efficacy of the injection mucosa knife (IMK) in ESD for rectal NETs. Methods: This retrospective study analyzed data from patients with rectal NETs undergoing ESD at three tertiary hospitals from January 2021 to December 2024, with 86 cases in the IMK group and 74 cases in the traditional Dual knife (DK) group. Primary endpoints comprised operative time, R0 resection rate, and complication incidence. Logistic regression was used to identify risk factors for positive vertical margins. Results: 21.6%, P=0.007) than the DK group, while R0 resection and postoperative complication rates were similar (P>0.05). Univariate analysis identified muscularis propria invasion as a risk factor for positive vertical margins. Conclusions: In the ESD treatment of rectal NETs, the IMK can shorten operative time and reduce muscular layer injury compared to the traditional DK. Moreover, it achieves a low incidence of postoperative complications, making it worthy of clinical promotion and application.