Full Spectrum vs. Standard Forward-viewing Colonoscopy

Study Overview
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Brief Summary
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The aim of this study is to evaluate FUSE-colonoscopy in terms of feasibility and its possible additive contribution in the detection of important lesions, namely polyps and cancers, compared to the standard forward-viewing approach, with and without the addition of the right-colon retroflexion technique, in a series of patients undergoing back-to-back screening or surveillance colonoscopies in a randomized fashion.

Detailed Description
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We changed the anticipated number of subjects enrollment for study: NCT02117674 from 120 to 200 based on the following sample size estimation: Tandem colonoscopies studies results, show that novel endoscopic technologies detect about 20% more adenomas than those conventional colonoscopy does (missed adenomas). Since FUSE colonoscopy cannot be considered as a perfect examination, we hypothesize that conventional colonoscopy will detect one third of the missed adenomas that FUSE detects in a similar setting. Therefore a sample size of 120 adenomas achieves 80% power to detect an odds ratio of 3.0 using a two-sided McNemar test with a significance level of 0.05. The odds ratio is equivalent to a difference between two paired proportions of 14% which occurs when the proportion of detected missed adenomas during FUSE is 21% and the proportion of missed adenomas during conventional colonoscopy is 7%. During one year period before the study initiation, our colonoscopy performance quality data show that we detect a mean number of adenomas per patient equal of 0.7 in a population similar to the one recruited in our study. Therefore, 172 patients overall will be required to detect 120 adenomas. Given the uncertainty of our estimation and in order to cope with patients exclusions, withdrawals and unexpected incomplete colonoscopies, we decided to recruit 200 patients. A more extensive description regarding the investigators study is provided in the following fields.

Official Title
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Full Spectrum vs. Standard Forward-viewing Colonoscopy With and Without Right-colon Retroflexion: a Randomized, Bicentric Back-to-back Study

Conditions
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Colon Neoplasms

Intervention / Treatment
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* Procedure: standard forward-viewing colonoscopy
* Procedure: full-spectrum colonoscopy
* Procedure: right colon retroflexion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults undergoing elective screening or surveillance colonoscopy symptomatic adults with indication for colonoscopy Exclusion Criteria: age over 80 years poor overall health (ASA III, IV) recent abdominal surgery presence of abdominal wall hernias active colitis multiple right colon diverticula previous bowel resection inflammatory bowel disease polyposis syndromes

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: standard forward-viewing colonoscopy<br>polyp detection with standard forward-viewing colonoscopy polyp detection in the right colon with scope retroflexion | Procedure: standard forward-viewing colonoscopy<br>* examination of the colon with a conventional colonoscope<br>* Other names: conventional colonoscopy;Procedure: full-spectrum colonoscopy<br>* examination of the colon with full-spectrum colonoscope<br>* Other names: fuse endoscopy;Procedure: right colon retroflexion<br>* examination of the right colon with scope retroflexion (both with conventional and fuse scope)<br>* Other names: retroflexion;|
| Active Comparator: full-spectrum colonoscopy<br>polyp detection with full-spectrum colonoscopy polyp detection in the right colon with scope retroflexion | Procedure: standard forward-viewing colonoscopy<br>* examination of the colon with a conventional colonoscope<br>* Other names: conventional colonoscopy;Procedure: full-spectrum colonoscopy<br>* examination of the colon with full-spectrum colonoscope<br>* Other names: fuse endoscopy;Procedure: right colon retroflexion<br>* examination of the right colon with scope retroflexion (both with conventional and fuse scope)<br>* Other names: retroflexion;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| polyp detection rate | per colon segment and for the entire colon | one week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| colonoscopy completion | colonoscopy completion rate | one week | 
| procedure time | intubation and withdrawal time | one week | 
| adverse events | adverse events rate | one week | 
| endoscopist's satisfaction | endoscopist's satisfaction quantified using a scale from 0 (not satisfied) to 10 (completely satisfied) | one week | 
| feasibility of the retroflexion in the right colon by trainee | feasibility of retroflexion in the right colon by trainee, meaning if the trainee managed to perform the right colon retroflexion or not | one week | 
| feasibility of retroflexion in the right colon by the consultant | feasibility of retroflexion in the right colon by the consultant, meaning if the consultant managed to perform the right colon retroflexion or not | one week | 
| patients' satisfaction | patients' satisfaction, quantified using a scale from 0 (not satisfied at all) to 10 (completely satisfied) | one week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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colonoscopy, adenoma detection rate, full spectrum colonoscopy, right colon retroflexion, feasibility