Endoscopic Resection for Small Rectal Neuroendocrine Tumors

Study Overview
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Brief Summary
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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.

Detailed Description
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Investigators aimed to conduct a muticenter randomized controlled trial to compare mEMR-C with ESD for the treatment of small rectal neuroendocrine tumors (NETs) in six tertiary hospitals in China.

Official Title
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Modified Cap-assisted Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection for Small Rectal Neuroendocrine Tumors Less Than 1 cm: a Muticenter Randomized Noninferiority Trial

Conditions
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Rectal Neuroendocrine Tumor

Intervention / Treatment
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* Procedure: mEMR-C procedure
* Procedure: ESD procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age from 18 to 75 years; With a high suspicion or evidence of rectal NET assessed using EUS or colonoscopy; With tumor size ≤10 mm assessed by colonoscopy; Plan to receive mEMR-C or ESD treatment and provide written informed consent; Exclusion Criteria: Unable to tolerate ESD or MEMR-C as assessed by the research team of each center; Complicated with serious diseases such as malignant tumor, which may lead to shorter life expectancy, the research team considers that it is not suitable for inclusion in the study after comprehensive evaluation; Rectal NET with lymph node metastasis or distant metastasis; Received resection of rectal neuroendocrine tumor by other surgical procedures; Multiple rectal neuroendocrine tumors; Vulnerable groups such as pregnant women or patients with mental disorders; Poor compliance, unable to cooperate with treatment.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: mEMR-C group<br>In mEMR-C group, enrolled patients will receive modified EMR-C without submucosal injection. | Procedure: mEMR-C procedure<br>* A transparent cap with an inner groove (MH-593; Olympus, Tokyo, Japan) was attached to the forward-viewing colonoscope. After the endoscope was inserted into the rectum, a crescent-shaped electrosurgical snare was passed through the sheath and looped along the inner groove of the cap. Submucosal injections were not required in this method. The tumor was suctioned into the cap and grasped by tightening the snare. After confirming the appropriate snare placement, both the tumor and overlying mucosa were resected using electric cautery (Endocut Q, effect 2, VIO 200D; ERBE, Tübingen, Germany), and the resected tumor was sent for pathological examination. Endoscopic examination was repeated without a transparent cap to evaluate the wound carefully in cases of perforation or bleeding and to ensure the absence of residual tumor tissues. If there was spurting or active bleeding, hot forceps were used to stop the bleeding.<br>|
| Active Comparator: ESD group<br>In ESD group, enrolled patients will receive the standard treatment modality of ESD to remove the rectal NET | Procedure: ESD procedure<br>* ESD was performed as the standard procedure and has been widely described and used. First, dots were marked approximately 5 mm from the periphery of the lesion using coagulation. Subsequently, a diluted sodium hyaluronate solution with indigo carmine dye was injected submucosally. Mucosal incision and submucosal dissection were performed using a T-Type ESD Knife (Micro-Tech, Nanjing, China) or Dual-knife (Olympus Medical, Tokyo, Japan). After resection was completed, all visible vessels on the artificial wound were thoroughly coagulated to prevent postoperative bleeding.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| histological complete resection | complete single-piece (en bloc) resection of the targeted lesion with horizontal and vertical free margins. | within 14 days after procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| success rate of operation | the proportion of patients whose tumors were successfully resected in each group | intraoperative | 
| en bloc resection | complete single resection of the targeted lesion, irrespective of whether the basal and lateral tumor margins were infiltrated or undetermined | intraoperative | 
| operation time | the time required to complete the procedure, was taken from the installation of the snare in the mEMR-C or the first submucosal injection in ESD to the end of complete resection of the targeted area or a failure or complication of the procedure which required discontinuation | intraoperative | 
| complications | perforation or hemorrhage during or after operation. | within 14 days after procedure | 
| length of stay | calculated from the day of admission to day of discharge | within 14 days after procedure | 
| hospitalization cost | represent the hospital's costs of being hospitalized | within 14 days after procedure | 
| operation cost | the cost of mEMR-C or ESD procedures, except the cost of other endoscopic procedures | within 14 days after procedure | 
| histopathologic grade | NET grade 1, NET grade 2, NET grade 3, and NEC | within 14 days after procedure |