Underwater EMR vs. Conventional EMR for Large Non-pedunculated Colonic Polyp

Study Overview
=================
Brief Summary
-----------------
To analyse the efficacy and safety of two standard methods of endoscopic mucosal resection (EMR) for large non-pedunculated colorectal polyps, the investigators will compare submucosal injection-assisted endoscopic mucosal resection (SEMR) versus underwater endoscopic mucosal resection, without submucosal injection (UEMR).

Detailed Description
-----------------
Underwater endoscopic mucosal resection (UEMR) emerges as a variant of traditional resection, in which a submucosal cushion formation is not necessary. This technique was described in 2012 by Kenneth Binmoeller based on the physical floating effect of colonic mucous membrane by filling the colonic lumen using water instead of air. This floating effect conditions the natural separation of the colonic wall layers, allowing the distension of the submucosal space without the need to inject substances into it. On the other hand, performing resection in liquid medium conditions could drive the benefit of heat dissipation caused by the current, which would reduces thermal damage caused to the tissues.

Official Title
-----------------
Efficacy and Safety of Underwater Endoscopic Mucosal Resection Versus Conventional Endoscopic Mucosal Resection for the Treatment of Large Non-pedunculated Colonic Lesions. Multicentric Randomized Controlled Trial

Conditions
-----------------
Colonic Polyp

Intervention / Treatment
-----------------
* Procedure: Underwater EMR
* Procedure: Conventional EMR


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Consecutive patients aged >18 years, diagnosed with a large (>=20 mm) non-pedunculated colonic polyp, who consent to endoscopic mucosal resection of the polyp and willing to participate in this study. Exclusion Criteria: Polyps showing signs of deep submucosal invasion Inflamatory bowel disease with signs of activity Known or suspected pregnancy Patients unable or unwilling to provide informed consent

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Underwater EMR<br>The patients randomized in this arm will be treated by endoscopic resection assisted by the filling of the colonic lumen using water instead of air and avoiding the formation of a submucosal cushion | Procedure: Underwater EMR<br>* Polypectomy is performed under full water emersion avoiding the use of submucosal injection.<br>|
| Active Comparator: Conventional EMR<br>The patients randomized in this arm will be treated by endoscopic resection following the traditional technique. It means, by assistance of selective submucosal saline injection to create a submucosal cushion below the polyp. | Procedure: Conventional EMR<br>* It will be performed in a 2-step procedure. First the formation of a submucosal injection underneath the polyp to create a submucosal safety cushion. Then EMR is performed with a polipectomy snare.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lesion recurrence rate | Presence of polyp tissue at the same site as the original lesion (adenoma or sessile serrated polyp) | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Technical success rate | Complete removal of polypoid tissue during the procedure | 1 hour | 
| Incidence of Treatment-Emergent Adverse Events | Incidence of Treatment-Emergent Adverse Events (delated hemorrhage, perforation, hospital admission) | 1 year | 
| En bloc Resection rate | Rate of endoscopic mucosal resection in one piece during the procedure | 1 hour | 
| Procedure time | Time in minutes for the endoscopic mucosal resection | 1 hour | 
| Number of fragments | Number of fragments of the endoscopic mucosal resection | 1 hour | 
| Lesion size | Size of the lesion in millimeters | 1 hour | 
| Thermal artecfacts |  | 1 hour | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Endoscopic mucosal resection, Colonic Polyp