BLI for the Diagnosis of Precancerous Conditions

Introduction: Traditionally, White Light Endoscopy (WLE), enhanced by biopsies following the updated Sydney system guidelines, has been the benchmark for diagnosing and classifying gastric preneoplastic conditions. Nevertheless, the pronounced interobserver variability and the often weak correlation between endoscopic observations and histopathological results have driven the increasing adoption of virtual chromoendoscopy (VCE). VCE technologies have demonstrated greater effectiveness in identifying these conditions compared to WLE, with Narrow Band Imaging (NBI) being particularly notable. Significantly, NBI has played a key role in validating the Endoscopic Grading of Gastric Intestinal Metaplasia (EGGIM) system. However, data on the effectiveness of other VCE technologies in this domain is relatively sparse in Europe, specifically with Blue Light Imaging (BLI), despite the promising diagnostic performance demonstrated with this technology. Primary aim: to assess the diagnostic accuracy of BLI and to externally validate the applicability of EGGIM classification for staging GIM. Material and methods: a multicentric cohort study will be performed involving centres from two European countries (Portugal, Italy). Consecutive patients performing upper gastrointestinal endoscopy will be evaluated by WLE and BLI. Random biopsies or targeted plus random biopsies will be performed in order to determine de accuracy of BLI system to detect and stage GIM. Expected results: We anticipate that BLI would enable us to assess the extension of GIM without the need for biopsies. If observed, this would overall improve the upper GI endoscopy accuracy.