Beyond the SCENIC route: updates in chromoendoscopy and dysplasia screening in patients with inflammatory bowel disease

Patients with Crohn's disease affecting the colon and ulcerative colitis are known to be at increased risk for the development of dysplasia and colorectal cancer (CRC). 1 Freeman H.J. Colorectal cancer risk in Crohn's disease. World J Gastroenterol. 2008; 14: 1810-1811 Crossref PubMed Scopus (52) Google Scholar ,2 Eaden J.A. Abrams K.R. Mayberry J.F. The risk of colorectal cancer in ulcerative colitis: a meta-analysis. Gut. 2001; 48: 526-535 Crossref PubMed Scopus (2102) Google Scholar Unlike patients with sporadic CRC, patients with longstanding inflammatory bowel disease (IBD) who develop malignancy do so through different pathophysiologic mechanisms and with foreshortened time frames. 3 Foersch S. Neurath M.F. Colitis-associated neoplasia: molecular basis and clinical translation. Cell Mol Life Sci. 2014; 71: 3523-3535 Crossref PubMed Google Scholar ,4 Ullman T. Croog V. Harpaz N. et al. Progression of flat low-grade dysplasia to advanced neoplasia in patients with ulcerative colitis. Gastroenterology. 2003; 125: 1311-1319 Abstract Full Text Full Text PDF PubMed Scopus (315) Google Scholar Furthermore, the gross appearance of dysplasia exhibits greater morphologic range in IBD patients, with subtler, flat lesions being commonplace. 5 Marion J.F. Sands B.E. The SCENIC consensus statement on surveillance and management of dysplasia in inflammatory bowel disease: praise and words of caution. Gastroenterology. 2015; 148: 462-467 Abstract Full Text Full Text PDF PubMed Scopus (33) Google Scholar Reassuringly, in the era of biologic therapies, rates of IBD-related CRC and CRC-associated mortality have declined. 6 Soderlund S. Brandt L. Lapidus A. et al. Decreasing time-trends of colorectal cancer in a large cohort of patients with inflammatory bowel disease. Gastroenterology. 2009; 136 (quiz 818-9): 1561-1567 Abstract Full Text Full Text PDF PubMed Scopus (183) Google Scholar This shift in prevalence has coincided with improved colonoscopic resolution and the adoption of adjunct surveillance techniques such as dye-spray chromoendoscopy (DCE). These therapeutic advances have been embraced by all societal IBD surveillance guidelines, but have also sown confusion among practicing gastroenterologists as to the best surveillance strategy to prevent colon cancer in IBD patients.