Optivista : I-SCAN OE for Optical Diagnosis of Small Colon Polyps
Condition: Colo-rectal Cancer; Polyps of Colon
MeSH terms: Polyps; Colonic Polyps
Study type: Observational

Summary: 
      This prospective randomized clinical trial aims to evaluate the new Optivista system compared
      to the iScan for his optical diagnosis and interval agreement monitoring with pathology. The
      Participants will be randomized to be diagnosed by either Optivista or Pentax iScan, and all
      polyps detected during the procedure, their size, location and morphology will be recorded
      according to the Paris classification after which all polyps will be resected per standard
      practices and sent for histopathologic evaluation. Further optical assessments will be
      performed for all polyps of 1-10 mm in size (WASP, NICE, SANO and SIMPLE classification)
      after with an analysis of comparison between optical diagnosis and pathology results will be
      performed.
    

Detailed description: 
      The benefit of colonoscopy screening is based on the detection and removal of polyps
      neoplastic. However, the vast majority of found polyps do not harbor any risk of non-cancer
      neoplastic. The resection evaluation and histopathology of these polyps are associated with
      costs while the contribution to cancer prevention is limited. A new technique (Pentax
      Optivista) based on visual diagnosis of polyps has been introduced to reduce the costs
      associated with over-screening, and seems to be more efficient than the Pentax iScan
      technique.

      This research project aims to evaluate the new Optivista system compared to the iScan for his
      optical biopsy performance and interval agreement monitoring with pathology.

      This is a prospective clinical trial for which participants are recruited directly from the
      colonoscopy clinic. The Participants will be randomized to be diagnosed by either Optivista
      or Pentax iScan. Endoscope withdrawal will be done in iScan 1 mode for patients randomized to
      iSan and in Optivista OE2 mode for patients randomized to Optivista.

      For all polyps detected during the procedure, their size, location and morphology will be
      recorded according to the Paris classification after which all polyps will be resected per
      standard practices and sent for histopathologic evaluation.

      Polyps that are between 1-10mm in size (diminutive and small polyps), there will be further
      assessed according to WASP, NICE, SANO and SIMPLE classifications using white light imaging
      and using an image-enhancing endoscopy technology that enhances visualisation of the polyp
      surface and vascular patterns.

      Concordance between optical diagnosis and pathology monitoring according to recommendations
      will be presented as proportions with a 95% CI. The features optical polyp diagnostic test
      for overall diminutive (1-5mm) polyps and by location in the colon (proximal, distal, colon
      and rectosigmoid segments) will be presented. For outcome measures secondary factors,
      including factors that may influence the optical diagnosis, proportional estimates with a 95%
      confidence interval (CI) will be presented. Concordance between strategies is examined using
      a marginal homogeneity test (Stuart-Maxwell test). For the comparison of proportions, a chi
      square test or a Fisher's exact two-sided test will be used, as appropriate.
    

Intervention name(s): Screening colonoscopy according to resect-and-discard strategy
Intervention type(s): Diagnostic Test
Intervention description(s): This strategy uses image enhancing techniques and optical diagnosis instead of histopathology assessment with 2 Pentax optical imaging systems (either Optivista or iScan).
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Participants will be recruited at the endoscopy unit at the CHUM, before undergoing an
        elective colonoscopy.
      
Biospecimen description: 
      Biopsy of colorectal polyps detected during the observed colonoscopy.
    
Keywords: Cancer prevention; Endoscopy; Gastroenterology