S876 Utility of Pancolonic Dye Spray Chromoendoscopy for Dysplasia Detection and Management in Inflammatory Bowel Diseases

Introduction: Patients with inflammatory bowel disease (IBD) involving the colorectum are at increased risk for the development of flat and poorly delineated dysplastic lesions. Pancolonic dye spray chromoendoscopy (DCE) is an adjunct to white light endoscopy (WLE) that enhances detection and delineation of such lesions. We evaluated the utility of DCE for lesion detection and/or management in patients with IBD who had visible (polypoid or flat lesions) or invisible (identified in non-targeted biopsies) dysplasia detected during high-definition (HD)-WLE. Methods: We retrospectively studied patients with colonic IBD from The Ottawa Hospital (Ottawa, Canada) who underwent DCE by a trained endoscopist, as follow-up for dysplasia detected during HD-WLE over a 7-year period (2013-2020). We assessed the ability of DCE to permit visualization of previously unidentified or poorly defined dysplasia, or to facilitate complete resection of poorly delineated dysplastic lesions. Results: Twenty-four patients were included (mean age 56.7±13.8 years, 50.0% male, 70.8% ulcerative colitis, mean disease duration 18.0±11.0 years, 70.8% moderate or severe disease activity historically, 41.7% remote history of dysplasia, and 4.2% PSC). More than 70% of patients were referred for DCE following detection of invisible dysplasia; the remainder were referred for surveillance of poorly defined flat dysplastic lesions. The dysplasia detection rate was 41.7% in HD-WLE, compared to 70.8% for DCE. For patients referred for DCE following detection of invisible dysplasia, DCE identified visible dysplasia at the same site in 8/17 (47.1%) patients, and visible dysplasia at a different site in 6/17 (35.3%) patients. For patients without prior invisible dysplasia, DCE identified new visible dysplasia in 3/7 (42.9%) of patients. DCE upgraded the highest grade of dysplasia and diagnosed CRC in 8.3% of patients, which was missed on index HD-WLE. DCE was unable to facilitate lesion resection in 12.5% of patients referred for poorly defined dysplastic lesions due to advanced lesion characteristics. Conclusion: In this study, DCE demonstrated utility in allowing detection of previously invisible dysplastic lesions in 33.3% patients, and in identifying a higher grade of dysplasia in 8.3% of patients. Further studies are needed to validate our findings. Given the low costs and risks associated with DCE, surveillance of patients with uncertain dysplastic findings on WLE using DCE is advisable.