Curriculum review: colorectal cancer surveillance and management of dysplasia in IBD.

The significantly increased risk of colorectal cancer (CRC) in longstanding colonic inflammatory bowel disease (IBD) justifies the need for endoscopic surveillance. Unlike sporadic CRC, IBD-related CRC does not always follow the predictable sequence of low-grade to high-grade dysplasia and finally to invasive carcinoma, probably because the genetic events shared by both diseases occur in different sequences and frequencies. Surveillance is recommended for patients who have had colonic disease for at least 8-10 years either annually, every 3 years or every 5 years with the interval dependant on the presence of additional risk factors. Currently, the recommended endoscopic strategy is high-definition chromoendoscopy with targeted biopsies, although the associated lengthier procedure time and need for experienced endoscopists has limited its uniform uptake in daily practice. There is no clear consensus on the management of dysplasia, which continues to be a challenging area particularly when endoscopically invisible. Management options include complete resection (and/or referral to a tertiary centre), close surveillance or proctocolectomy. Technical advances in endoscopic imaging such as confocal laser endomicroscopy, show exciting potential in increasing dysplasia detection rates but are still far from being routinely used in clinical practice.