If complete resection is achieved with MAPK inhibitor negative biopsies from the flat mucosa immediately adjacent to the polypectomy site, and no dysplasia is found elsewhere in the colon, close endoscopic surveillance, preferably with chromoendoscopy, at 3 months and then at least annually is appropriate. An unresectable lesion or a lesion with dysplasia in the adjacent mucosa is an indication for colectomy. If dysplasia is not associated with a visible lesion, but is found on random biopsy, repeat evaluation with chromoendoscopy by an experienced endoscopist is warranted

to assess for a visible and resectable dysplastic lesion and to evaluate for synchronous dysplasia; in this case, random biopsies may be indicated.18 These guidelines highlight that the most important feature of well-circumscribed, detected lesions is endoscopic

resectability, with confirmation that adjacent mucosa is negative for dysplasia. Older guidelines follow similar recommendations using different terminology. The definition of endoscopic resectability will continue to evolve. Consensus is needed to standardize the terminology of detected dysplastic lesions and dysplasia detected by random biopsies not associated with an endoscopically this website visible lesion. Additional consensus is required to determine optimal surveillance after a dysplastic lesion is resected, and how or if the degree of dysplasia should influence the surveillance interval. While endoscopically invisible high-grade dysplasia is universally considered an indication for colectomy, the approach to low-grade dysplasia needs further clarification. Endoscopically visible lesions that are well circumscribed before and amenable to resection, with no evidence of dysplasia in the

surrounding mucosa or elsewhere in the colon on nontargeted biopsies, are appropriate for continued colonoscopic surveillance. Surveillance colonoscopy is indicated in patients with left-sided or extensive UC, and in patients with Crohn’s colitis with involvement of more than 1 colonic segment. The goal of surveillance is to detect dysplasia and to prevent IBD-CRN. Risk factors for IBD-CRN that influence screening and surveillance intervals require further study. To maximize dysplasia detection, European society guidelines endorse chromoendoscopy with targeted biopsies, although societies in the United States have yet to endorse chromoendoscopy as the preferred method for IBD-CRN surveillance. The European guidelines endorsing chromoendoscopy do not require random biopsies of normal-appearing colonic mucosa. However, the role of random biopsies for dysplasia detection needs to be clarified in the setting of inflammation or in areas of pseudopolyps, when the yield of chromoendoscopy may be decreased.