From the Guidelines
Screening colonoscopy in inflammatory bowel disease (IBD) patients should begin 8-10 years after disease onset, with subsequent surveillance intervals determined by risk stratification. For the procedure, patients should undergo thorough bowel preparation using a split-dose regimen of polyethylene glycol solution. During colonoscopy, high-definition endoscopes with chromoendoscopy (using indigo carmine or methylene blue dye spray) should be employed to enhance detection of dysplastic lesions, as recommended by the AGA clinical practice update on endoscopic surveillance and management of colorectal dysplasia in inflammatory bowel diseases: expert review 1.
The endoscopist should perform a systematic examination of the entire colon with four-quadrant biopsies every 10 cm in the colon, with additional targeted biopsies of any suspicious areas. Ideally, the colonoscopy should be performed during disease remission to improve visualization and reduce false positives from inflammation. Patients with primary sclerosing cholangitis require annual surveillance regardless of disease duration. For moderate to high-risk patients (extensive colitis, family history of colorectal cancer, presence of pseudopolyps, or strictures), surveillance should occur every 1-3 years, while low-risk patients can be screened every 5 years, as suggested by the AGA clinical practice update on endoscopic surveillance and management of colorectal dysplasia in inflammatory bowel diseases: expert review 1.
Some key points to consider during the procedure include:
- Using a modified Paris Classification to describe precancerous colorectal lesions 1
- Optimizing conditions and practices for dysplasia detection, including control of inflammation, use of high-definition endoscopes, bowel preparation, careful washing and inspection of all colorectal mucosa, and targeted sampling of any suspicious mucosal irregularities 1
- Considering dye spray chromoendoscopy or virtual chromoendoscopy for dysplasia detection in persons with colonic inflammatory bowel disease 1
- Taking extensive nontargeted biopsies (roughly 4 adequately spaced biopsies every 10 cm) from flat colorectal mucosa in areas previously affected by colitis when white light endoscopy is used without dye spray chromoendoscopy or virtual chromoendoscopy 1
This intensive surveillance protocol is necessary because IBD patients have a 2-3 times higher risk of developing colorectal cancer compared to the general population, with risk increasing with disease duration, extent, and severity of inflammation. The most recent and highest quality study, the AGA clinical practice update on endoscopic surveillance and management of colorectal dysplasia in inflammatory bowel diseases: expert review 1, provides the best guidance on this topic.
From the Research
Protocol for Screening Colonoscopy in Patients with Inflammatory Bowel Disease (IBD)
The protocol for performing a screening colonoscopy in patients with IBD involves several key steps and considerations, as outlined in recent studies 2, 3, 4, 5, 6.
- Initial Screening: The first screening colonoscopy should be offered 8 to 10 years after the onset of disease symptoms in patients with at least left-sided ulcerative colitis or Crohn's disease involving more than 30% of the colon 2, 3.
- Surveillance Intervals: Patients should be stratified according to their individual risk for endoscopic surveillance intervals, which can range from one to five years depending on the presence of risk factors and guidelines employed 2, 3.
- Endoscopic Techniques: Chromoendoscopy with targeted biopsies is currently the recommended method for detecting dysplasia in screening colonoscopies in IBD patients, although virtual chromoendoscopy is emerging as a potential alternative 4, 5, 6.
- Lesion Detection and Management: Visible lesions should be endoscopically resected, and surgery should only be recommended when a complete resection is not possible 6.
- High-Risk Patients: Patients with concomitant primary sclerosing cholangitis are at an additionally increased risk and should undergo annual surveillance starting immediately after diagnosis 2.
Special Considerations
- Risk Stratification: Patients should be stratified according to their individual risk for endoscopic surveillance intervals, taking into account factors such as disease extent, duration, and presence of primary sclerosing cholangitis 2, 3.
- Technological Advances: Advances in endoscopic techniques, such as virtual chromoendoscopy and confocal laser endomicroscopy, may improve the detection and management of dysplastic lesions in IBD patients 4, 5, 6.