A Simplified Endoscopic Grading Model for Gastric Intestinal Metaplasia With Preserved Diagnostic Accuracy

The endoscopic grading of gastric intestinal metaplasia (EGGIM) score enables real-time endoscopic assessment of the extent and severity of gastric intestinal metaplasia (IM) to guide surveillance.

We aimed to simplify the EGGIM system by identifying key gastric sites and evaluating simplified scoring approaches.

In this retrospective cohort study, patients undergoing gastric mapping during gastroscopy from 2022 to 2024 at a medical center were analyzed. EGGIM scoring was performed in real-time using high-resolution narrow-band imaging, with histopathological confirmation. We evaluated EGGIM-S, a simplified score based on the incisura angularis and the corpus lesser curvature. The diagnostic performance in predicting advanced IM (OLGIM Stage III/IV) was assessed and compared with the original EGGIM score.

Among 942 patients undergoing mapping biopsies (56% female; median age 64 years), endoscopic IM involvement at the incisura angularis (odds ratio [OR] 1.75; p = 0.039) and the corpus lesser curvature (OR 2.54; p < 0.001) was independently associated with advanced histological stage, whereas involvement at the other sites was not. Combining these two sites, the AUROC was 0.829 for EGGIM-S and 0.828 for the original EGGIM, meeting the prespecified noninferiority margin (0.03; p = 0.0054).

Intestinal metaplasia involving the corpus lesser curvature and the incisura angularis was significantly associated with advanced histological stage. A simplified two-site model (EGGIM-S) demonstrated comparable diagnostic performance, with the potential to improve efficiency and clinical applicability.