Chromoendoscopy versus narrow band imaging in UC: a prospective randomised controlled trial

Background Patients with long-standing UC have an increased risk for the development of colonic neoplastic lesions. Chromoendoscopy (CE) has been proven to enhance neoplasia detection while the role of virtual chromoendoscopy (VC) is still to be defined. Objective To compare the performance of CE to VC for the detection of neoplastic lesions in patients with long-standing UC. Design A multicentre prospective randomised controlled trial. 131 patients with long-standing UC were randomised between CE with methylene blue 0.1% (n=66) or VC with narrow band imaging (NBI) (n=65). Biopsies were taken from visible lesions and surrounding mucosa. No random biopsies were performed. The primary outcome was the difference in total number of neoplastic lesions detected in each group. Results There was no significant difference between NBI and CE for neoplasia detection. Mean number of neoplastic lesions per colonoscopy was 0.47 for CE and 0.32 for NBI (p=0.992). The neoplasia detection rate was not different between CE (21.2%) and NBI (21.5%) (OR 1.02 (95% CI 0.44 to 2.35, p=0.964). Biopsies from the surrounding mucosa yielded no diagnosis or dysplasia. The per lesion neoplasia detection was 17.4% for CE and 16.3% for NBI (OR 1.09 (95% CI 0.59 to 1.99, p=0.793). The total procedural time was on average 7 min shorter in the NBI group. Conclusion CE and NBI do not differ significantly for detection of colitis-associated neoplasia. Given the longer withdrawal time for CE and easier applicability, NBI may possibly replace classical CE. Trial registration number NCT01882205; Results.