Endoscopic grading of gastric intestinal metaplasia (EGGIM): a multicenter validation study

Background: Random biopsies are recommended to identify individuals at risk for gastric adenocarcinoma. Cumulative evidence suggests that narrow-band imaging (NBI) can be used to grade gastric intestinal metaplasia (GIM). We aimed to externally validate a classification of endoscopic grading of gastric intestinal metaplasia (EGGIM). Methods: Consecutive patients in 2 centers were submitted to high-resolution white light gastroscopy followed by NBI to estimate EGGIM – a score (0-10) resulting of the sum of endoscopic assessment of GIM (0, 1 or 2 if no GIM, <30% or >30% of the mucosa, respectively) in 5 areas (lesser and greater curvature of both antrum and corpus and incisura). If GIM was endoscopically suspected, targeted biopsies were performed; if GIM was not noticeable, random biopsies according to Sydney-system were performed to estimate OLGIM (gold-standard). Results: 250 patients (62% female; median age 55 years) were included. GIM was staged as OLGIM 0, I, II, III, IV: 136(54%), 15(6%), 52(21%), 34(14%), 13(5%), respectively. All sites and patients (except 3) with GIM were identifiable with targeted biopsies. For the diagnosis of OLGIM III-IV, the area under the ROC curve was 0.97 (95%CI 0.95–0.99) and by using a cutoff >4, sensitivity, specificity, LR+ were 89%, 95%, 16.5, respectively; results (91%, 95%, 18.1) similar when excluding patients with foveolar hyperplasia. Conclusions: For the first time, an endoscopic approach was externally validated to determine the risk for gastric cancer without the need of biopsies. This can be used to simplify and individualize the management of patients with gastric precancerous conditions.