Optical Diagnosis Versus Laser Measurement of Polyps' Size During Colonoscopy and Implications for Surveillance

Study Overview
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Brief Summary
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Recent updates of the guidelines on polyp surveillance of the American Society of Gastrointestinal Endoscopy (ASGE) and European Society of Gastrointestinal Endoscopy (ESGE) increasingly focus on size of polyps as an important indicator of malignant transformation to colorectal cancer (CRC). However, the interobserver variability in polyp size assessment between optical diagnosis of endoscopists and pathologists is considerable. This may lead to incorrect surveillance intervals in patients at risk for developing colorectal cancer, which may increase the risk of post-colonoscopy CRC (PCCRC). This study aims to assess the precision of a new laser-based measurement system (AccuMeasure, VTM Technologies Ltd.) for polyps during colonoscopy.

Detailed Description
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Objective: The main objective is to compare the precision of polyp size measurement by AccuMeasure to biopsy forceps assisted measurement. Secondary objectives are to assess: Time needed for measurement and learning curve, endoscopists advised surveillance intervals based on both measurement methods, and safety. Study design: Multicenter, randomized, parallel group, endoscopist blinded study, including the measurement of 138 polyps during standard colonoscopy. With a polyp detection rate of approximately 40%1, this results in up to 345 patients/colonoscopies to be included. Enrollment will conclude once 138 polyps are included in the study. Study population: All adult patients with screening or surveillance colonoscopies will be asked for informed consent. Polyps smaller than 25mm found during colonoscopy are considered eligible for inclusion. Up to 3 polyps per patient can be included in this study. Intervention: Optical assessment will be performed upon identification of the polyp. Then, measurement with AccuMeasure and biopsy forceps will be performed in a randomized order. The endoscopist will remain blinded to the AccuMeasure measurement outcomes, to avoid a learning effect that could influence subsequent measurements.

Official Title
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Optical Diagnosis Versus Laser Measurement of Polyps' Size During Colonoscopy and Implications for Surveillance (Polyp Size Study)

Conditions
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Colorectal Polyp

Intervention / Treatment
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* Device: AccuMeasure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Adult patients (>18 years) Scheduled for screening, surveillance, or diagnostic colonoscopy Polyps of all forms ≤ 25mm as assessed by the endoscopist Exclusion Criteria: • Therapeutic colonoscopy; Inflammatory bowel disease (IBD); American Society of Anesthesiologists (ASA) score of >3; Inadequately corrected anticoagulation disorder or anticoagulation medication use; Inability to provide informed consent; Inadequate bowel preparation (Boston bowel preparation scale score [BBPS] <2 per segment); No polyps identified during colonoscopy or only small (<5mm) hyperplastic rectal polyps; Intraprocedural complications, not caused by the study device.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: As optical assessment of polyps has a high interobserver variability, the order of polyps' size measurement using biopsy forceps or AM will be randomized per patient. Therefore, this study consists of two arms: Optical polyp size assessment, followed by biopsy forceps and then AM measurement (1), and optical assessment, followed by AM measurement and then biopsy forceps assisted assessment (2) (Figure 1).
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Accumeasure last<br>Optical polyp size assessment, followed by biopsy forceps and then AccuMeasure measurement | Device: AccuMeasure<br>* intracolonoscopy measurement of polyps using a laser-based device<br>* Other names: laser-based polyp measurement;|
| Other: AccuMeasure first<br>optical assessment, followed by AccuMeasure measurement and then biopsy forceps assisted assessment (2) | Device: AccuMeasure<br>* intracolonoscopy measurement of polyps using a laser-based device<br>* Other names: laser-based polyp measurement;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cohens' Kappa coefficient | interobserver agreement between AccuMeasure and biopsy forceps assisted measurement | at colonoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants with adverse events up to 30 days post colonoscopy | Number of Participants with adverse events | 30 days post colonoscopy | 
| Absolute size differences | Size differences for optical/biopsy forceps/AM assessment as compared to pathology size measurement; | at colonoscopy | 
| Time for measurement | Time for measurement with AccuMeasure related to number of measurements performed | at colonoscopy | 
| Endoscopist advised surveillance interval | Endoscopist advised surveillance interval based on optical assessment during colonoscopy, on measurement with an open biopsy forceps, and on measurement with AccuMeasure | At colonoscopy | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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screening, colonoscopy, surveillance