Clinical Significance of Reddish Depressed Lesions Observed in the Gastric Mucosa after Helicobacter pylori Eradication

Background and Aim: Reddish depressed lesions (RDLs) frequently observed in patients following Helicobacter pylori eradication are indistinguishable from gastric cancer. We examined the clinical and histological feature of RDLs and its relevant endoscopic diagnosis including magnifying narrow-band imaging (M-NBI). Methods: We enrolled 301 consecutive patients with H. pylori eradication who underwent endoscopy using white light imaging (WLI). We examined the prevalence and host factors contributing to the presence of RDLs. Next, we used M-NBI in 90 patients (104 RDLs), and compared the diagnostic efficacy between M-NBI and WLI groups using propensity-score matching analysis. Results: In 301 patients after eradication, 117 (39%) showed RDLs. Male, open-type atrophy, and gastric cancer history were risk factors for RDLs. A gastric biopsy was needed in 83 (71%) during WLI observation and only 2 were diagnosed with adenocarcinoma. In M-NBI group, a biopsy was performed in 21 (20%), and 9 were diagnosed with adenocarcinoma. A biopsy was required in fewer patients, and the positive predictive value of a biopsy was statistically higher in M-NBI than in the WLI group (p < 0.01). Conclusions: RDLs are frequently observed in high-risk patients for gastric cancer after eradication. M-NBI demonstrated significantly superior diagnostic efficacy with respect to RDL.