Editorial: Surveillance Colonoscopy for Detection of Neoplasia in Inflammatory Bowel Disease—Is Dye-Based Chromoendoscopy Always the Final Answer? Authors' Reply

Abstract

We appreciate the thoughtful editorial by Drs. Cassinotti and Canova [1], which raised pertinent questions about the landscape of endoscopic surveillance in inflammatory bowel disease (IBD).

Our network meta-analysis reviewed published data on IBD dysplasia detection technologies [2]. We acknowledge that significant heterogeneity exists. Our paper highlighted variability in protocols, nomenclature and patient populations, amongst others; this is the best that can be done with the available data. It reflected the inherent challenges in standardising large-scale surveillance studies in an evolving field. Notwithstanding the aforementioned limitations, the data deemed dye-based chromoendoscopy (DCE) superior.

While attractive for its ease of use, available data on virtual chromoendoscopy (VCE), particularly magnified narrow-band imaging, are limited. Until further evidence clarifies VCE's performance relative to DCE, we view it as a reasonable alternative in the absence of DCE expertise. Regarding confocal endomicroscopy, we agree that its utility is limited by a lack of commercialisation.

DCE's advantage is in revealing subtle, previously unmasked mucosal abnormalities [3, 4]. The editorial raises an interesting point regarding the ‘time factor’ or ‘devoted attention’ potentially contributing to DCE's effectiveness. The study by Toruner et al. investigated white light endoscopy (WLE) and suggested that longer procedural times may improve colonic representativeness through more evenly spaced random biopsies [5]. However, this pertains to flat dysplasia, an endoscopically invisible subtype detected primarily by random biopsies rather than active mucosal inspection. Thus, the increased time probably reflects stricter protocol adherence rather than a deliberate search for abnormalities.

Indeed, initial results of high-definition WLE with segmental re-inspection (HDWLE-SR) are drawn from one promising study [6]. If proven to be a successful alternative to DCE, it could simplify workflows and encourage wider adoption, considering endoscopists' familiarity with HD-WLE. Segmental re-inspection may exemplify the ‘attention’ that enhances detection. HDWLE-SR's success may also stem from being conducted primarily at expert centres with highly experienced IBD endoscopists, increasing the likelihood of identifying missed regions upon re-inspection. Nonetheless, replication and validation are necessary before reaching strong conclusions.

Given WLE's limitations in detecting flat lesions, current guidelines recommend random four quadrant and targeted biopsies [7]. Yet, DCE and VCE comparators often employ targeted-only approaches. Perhaps the real clinical utility of DCE or VCE lies in reducing the biopsy burden for patients, endoscopists and pathologists while maintaining diagnostic performance. The value of non-targeted biopsies has been questioned [8]. Would the data on DCE give us the confidence to finally embrace a fully targeted-only approach? Is it time to risk-stratify diagnostic techniques as we are doing with surveillance intervals [9]? Would the discussion shift from techniques with the highest marginal detection rates to ones more focused on cost–benefit analyses? These questions warrant further study.

Network meta-analyses shed light on comparative superiority but remain hypothesis-generating. The field remains dynamic, with ongoing studies like a large Canadian IBD dysplasia study and new data being presented at ECCO 2025. It is unclear if DCE will remain superior as new imaging technologies in the era of artificial intelligence have not yet been adapted to IBD.