Unveiling cancer in IBD: screening colonoscopy or chromoendoscopy

The risk of developing colorectal cancer (CRC) is increased in patients with inflammatory bowel disease (IBD), particularly if the disease is extensive and its duration long-standing. Endoscopic guidelines have been developed with the goal of detecting early neoplastic changes prior to development of advanced malignancy. The current surveillance strategy of surveillance colonoscopy, with multiple random biopsies, most likely reduces morbidity and mortality associated with IBD-related CRC. Unfortunately, standard surveillance colonoscopy also has limitations, including high cost and sampling error at time of biopsy. The main issue is that colitis associated neoplasms often occur in flat mucosa of normal appearance, and are detected on taking random biopsies rather than by direct identification of these lesions via endoscopic imaging. Advances in endoscopic imaging techniques, such as vital or optical chromoendoscopy, that can enhance mucosal characteristics, may potentially aid in increasing dysplasia detection rate, and may reduce the workload of standard random biopsies. The aim of this review was to describe and summarize outcomes of more advanced endoscopic imaging techniques, including chromoendoscopy and magnification endoscopy.