Implementation of Optical Diagnosis for Diminutive Polyps Amongst Endoscopists: Training and Long-term Quality Assurance
Condition: Colonoscopy; Colonic Polyps
MeSH terms: Polyps; Colonic Polyps
Study type: Observational

Summary: 
      In this study, Dutch gastroenterologists who are certified for performing colonoscopies on
      FIT-positive patients in the Dutch population screening program are trained in optical
      diagnosis with validated methods. After this training, an ex- and in-vivo test phase leads to
      "accreditation" and endoscopists will be observed in their optical diagnosis for 1 year.
      During this year, half of the endoscopists will be randomized towards 3-monthly feedback and
      the other half will receive feedback on their results after 1 year. The endoscopic prediction
      of endoscopists on polyp histology will be compared to histopathological outcome.
    

Detailed description: 
      Through the recently started nationwide bowel cancer screening programme in the Netherlands,
      an extra 70.000 colonoscopies are annually performed. In current practice, all resected
      colonic lesions are histopathologically analysed. Even diminutive polyps, which rarely
      harbour cancer or advanced histological features. If endoscopists are able to accurately
      differentiate between neoplastic and non-neoplastic lesions during colonoscopy, practice
      could become more efficient and costeffective. This strategy is called optical diagnosis and
      two clinical practice strategies have been proposed by the American Society of
      Gastroenterologists (ASGE). First, diminutive polyps could be resected and discarded if >90%
      of the surveillance intervals predicted on optical diagnosis correlate with the surveillance
      intervals after histopathological validation (if assessed with high confidence). Second,
      hyperplastic polyps in the rectosigmoid could be left in situ if endoscopists are able to
      confidently predict neoplastic histology of diminutive colorectal polyps with a negative
      predictive value (NPV) of ≥90%.

      The accuracy of white light colonoscopy is not acceptable for daily practice (59%-84%), but
      narrow band imaging (NBI) allows higher accuracies up to 98% and it was demonstrated that
      experienced endoscopists could reach a NPV of ≥90% for diminutive colorectal lesions.
      However, recent research shows that community gastroenterologists are not able to meet the
      quality thresholds proposed by the ASGE. Before this strategy could be safely applied in
      daily practice, community gastroenterologists should be able to meet thresholds as well.

      In this study, Dutch gastroenterologists who are certified for performing colonoscopies on
      FIT-positive patients in the Dutch population screening program, are trained in optical
      diagnosis with validated methods. After training, an ex- and in-vivo test phase leads to
      "accreditation" and endoscopists will be observed in their optical diagnosis for 1 year.
      During this year, half of the endoscopists will be randomized towards 3-monthly feedback and
      the other half will receive feedback on their results after 1 year. The endoscopic prediction
      of endoscopists on polyp histology will be compared to histopathological outcome.
    

Intervention name(s): Feedback
Intervention type(s): Behavioral
Intervention description(s): 3-monthly or no 3-monthly feedback on results of optical diagnosis
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Endoscopists certified for performing Dutch screening colonoscopies. Colonoscopies in
        patients performed after a positive FIT obtained for the Dutch colorectal cancer screening
        program.
      
Keywords: Optical diagnosis