Rectal Neuroendocrine Tumor

This prospective, randomized pilot study will compare traction-assisted endoscopic submucosal dissection (T-ESD) with conventional endoscopic submucosal dissection (C-ESD) for the treatment of rectal neuroendocrine tumors. Patients with rectal neuroendocrine tumors generally measuring 15 mm or less, without suspected muscularis propria invasion, lymph node metastasis, or distant metastasis, who are considered suitable for endoscopic resection will be eligible for enrollment. Participants will be randomly assigned in a 1:1 ratio to undergo either T-ESD or C-ESD. In the T-ESD group, a traction device will be used during submucosal dissection to improve visualization of the submucosal layer, whereas conventional ESD will be performed without routine use of a traction device. The primary outcome is resection speed, calculated as the resected specimen area divided by the submucosal dissection time. Secondary outcomes include total procedure time, submucosal dissection time, en bloc and R0 resection rates, resection margin status, procedure-related adverse events, length of hospital stay, time to diet resumption, and unplanned emergency department visits or readmissions. The study is designed as an exploratory pilot trial to estimate the efficacy, safety, and variability of traction-assisted ESD and to provide preliminary data for the design of a future larger multicenter randomized trial.

Underwater endoscopic mucosal resection (UEMR) and endoscopic submucosal dissection (ESD) have both been reported to be two effective treatment methods for small rectal neuroendocrine tumor (NET). However, there is no consensus on the best method for the endoscopic resection of rectal NET. Therefore, we aimed to compare the efficacy and safety of UEMR and ESD for the treatment of small rectal NET.

According to clinical practice and relevant retrospective research data, both modified cap-assisted endoscopic mucosal resection (mEMR-C) and endoscopic mucosal resection with a ligation device(ESMR-L) were reported to be effective for the treatment of small rectal neuroendocrine tumors (NETs) . However, there is a lack of multicenter prospective studies to evaluate the advantages and disadvantages of mEMR-C and mEMR-L. mEMR-C is the modified ESMR-L without submucosal injection.

In previous single center study, both modified cap-assisted endoscopic mucosal resection (mEMR-C) and endoscopic submucosal dissection (ESD) were reported to be effective for the treatment of small rectal neuroendocrine tumors (NETs) and mEMR-C was inferior to ESD for the treatment of small rectal NETs (≤10 mm), as it has shorter operation times and lower hospitalization costs. However, a multicenter randomized controlled trial is needed to prove the universality and generality of these findings.