Back-to-back Endoscopy Versus Single-pass Endoscopy and Chromoendoscopy in IBD Surveillance

Overview

The current international guidelines for CRC surveillance in IBD recommend as first choice the use of chromoendoscopy, and as an alternative high-definition white light endoscopy (HDWLE) for optimal dysplasia detection, based on data from clinical trials. However, data on the superiority of CE over HDWLE are not consistent in literature. The investigators hypothesize that the better performance of CE in some clinical trials is the result of the associated longer procedural time and the fact that every colon segment is examined twice. Currently, no studies have been published evaluating the dysplastic yield of back-to back HDWLE compared to HDWLE with a single pass or CE in patients with IBD. In the present study, the investigators aim to compare the yield of dysplasia/CRC between 1) regular HDWLE, 2) HDWLE back-to-back, and 3) CE.

The investigators assume based on previous research a yield of 12% using high-definition white light endoscopy and 24% using either chromoendoscopy or high-definition white light endoscopy with a second examination (Imperatore et al 2019). To show non-inferiority of back-to-back HDWLE compared to CE, with a non-inferiority margin of 10% (power 80% and alpha 5%,) a total of 226 patients per group is required. To demonstrate a superiority of back-to-back HDWLE compared to a regular HDWLE, with a 1:2 allocation ratio of single-pass vs back-to-back , 113 and 226 patients per group are needed to achieve 80% power with an alpha of 5%. Therefore, the investigators will include 226 patients in group back-to-back HDWLE, 226 in group CE, and 113 patients in group regular HDWLE. This amounts to a total of 560 patients. To account for any screen-failures The investigators will include at most 5% (of 560) additional patients until 80% power is reached.