Advances in endoscopic dysplasia detection in inflammatory bowel disease

Abstract

Background: Dysplasia surveillance in inflammatory bowel disease (IBD) has evolved significantly with the adoption of advanced endoscopic technologies.

Aim: To synthesize evidence on image-enhanced endoscopy techniques, biopsy protocols, and surveillance practices optimizing dysplasia detection in IBD.

Methods: A scoping review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search of PubMed and EMBASE from inception to June 2025 identified studies reporting on endoscopic dysplasia detection or characterization in IBD. Forty-five studies were included for qualitative synthesis, covering dye-based chromoendoscopy (DCE), virtual chromoendoscopy (VCE), confocal laser endomicroscopy, artificial intelligence-based tools, and panoramic endoscopy.

Results: DCE consistently demonstrated high dysplasia detection rates, especially when indigo carmine was used, and enabled accurate pit-pattern-based lesion characterization. High definition (HD) DCE may offer procedural benefits over HD white light endoscopy (WLE), though superiority in dysplasia detection remains inconsistent across studies. In comparative studies, DCE outperformed or matched white-light approaches, with higher dysplasia yield in selected trials (e.g., 9.7% vs 1.9%, P = 0.004), while HD WLE with segmental re-inspection was non-inferior to DCE in expert settings. Virtual chromoendoscopy modalities such as i-SCAN and narrow band imaging showed comparable performance to DCE in several trials, with artificial intelligence-assisted computer-aided detection systems demonstrating equivalent sensitivity but lower specificity. Studies comparing biopsy protocols revealed that targeted biopsies under image-enhanced endoscopy, particularly DCE, were generally superior or equivalent to random biopsies, with random sampling offering marginal benefit in select high-risk subgroups. Multimodal imaging and panoramic endoscopy further improved dysplasia yield in challenging cases. Cost-effectiveness analyses favored DCE over WLE, and long-term surveillance data confirmed declining colorectal cancer rates with high-quality endoscopic programs. However, real-world practice audits revealed substantial variation in surveillance quality and guideline adherence.

Conclusion: Image-enhanced targeted surveillance - particularly using DCE or validated virtual platforms - has improved dysplasia detection in IBD and may allow for a reduction in random biopsies. Despite technological advancements, major quality gaps and interobserver variability persist in clinical practice. Standardized training, quality benchmarks, and cost-effective implementation of advanced endoscopic techniques are needed to optimize colorectal cancer prevention in IBD.

Keywords: Biopsy; Colitis-associated neoplasia; Dye-based chromoendoscopy; Dysplasia; High-definition endoscopy; Narrow band imaging; Virtual chromoendoscopy; White light endoscopy.

Figure 1

Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 checklist.

Figure 2

Representative images of a Japanese Narrow band imaging Experts Team 2A/B lesion in the descending colon observed under dye-based chromoendoscopy. A: Methylene blue chromoendoscopy reveals a regular surface pattern with slight vascular irregularity, consistent with low-grade dysplasia features; B: Crystal violet staining enhances the pit pattern, demonstrating a type IV-VI Kudo pattern suggestive of possible high-grade dysplasia.