Toyoshima O, Nishizawa T. Kyoto classification of gastritis: Advances and future perspectives in endoscopic diagnosis of gastritis. World J Gastroenterol 2022; 28(43): 6078-6089 [PMID: 36483157 DOI: 10.3748/wjg.v28.i43.6078]
Corresponding Author of This Article
Osamu Toyoshima, MD, PhD, Director, Department of Gastroenterology, Toyoshima Endoscopy Clinic, Seijo 6-17-5, Setagaya-ku, Tokyo 157-0066, Japan. t@ichou.com
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Editorial
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Gastroenterol. Nov 21, 2022; 28(43): 6078-6089 Published online Nov 21, 2022. doi: 10.3748/wjg.v28.i43.6078
Kyoto classification of gastritis: Advances and future perspectives in endoscopic diagnosis of gastritis
Osamu Toyoshima, Toshihiro Nishizawa
Osamu Toyoshima, Toshihiro Nishizawa, Department of Gastroenterology, Toyoshima Endoscopy Clinic, Tokyo 157-0066, Japan
Toshihiro Nishizawa, Department of Gastroenterology and Hepatology, International University of Medicine and Welfare, Narita 286-8520, Japan
Author contributions: Toyoshima O and Nishizawa T contributed to this paper; Toyoshima O contributed to the design, writing of the manuscript, illustrations, and review of literature; Nishizawa T contributed to the design, discussion, and editing the manuscript.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Osamu Toyoshima, MD, PhD, Director, Department of Gastroenterology, Toyoshima Endoscopy Clinic, Seijo 6-17-5, Setagaya-ku, Tokyo 157-0066, Japan. t@ichou.com
Received: September 14, 2022 Peer-review started: September 14, 2022 First decision: October 3, 2022 Revised: October 6, 2022 Accepted: November 4, 2022 Article in press: November 4, 2022 Published online: November 21, 2022
Abstract
This editorial provides an update of the recent evidence on the endoscopy-based Kyoto classification of gastritis, clarifying the shortcomings of the Kyoto classification, and providing prospects for future research, with particular focus on the histological subtypes of gastric cancer (GC) and Helicobacter pylori (H. pylori) infection status. The total Kyoto score is designed to express GC risk on a score ranging from 0 to 8, based on the following five endoscopic findings: Atrophy, intestinal metaplasia (IM), enlarged folds (EF), nodularity, and diffuse redness (DR). The total Kyoto score reflects H. pylori status as follows: 0, ≥ 2, and ≥ 4 indicate a normal stomach, H. pylori-infected gastritis, and gastritis at risk for GC, respectively. Regular arrangement of collecting venules (RAC) predicts non-infection; EF, nodularity, and DR predict current infection; map-like redness (MLR) predicts past infection; and atrophy and IM predict current or past infection. Atrophy, IM, and EF all increase the incidence of H. pylori-infected GC. MLR is a specific risk factor for H. pylori-eradicated GC, while RAC results in less GC. Diffuse-type GC can be induced by active inflammation, which presents as EF, nodularity, and atrophy on endoscopy, as well as neutrophil and mononuclear cell infiltration on histology. In contrast, intestinal-type GC develops via atrophy and IM, and is consistent between endoscopy and histology. However, this GC risk-scoring design needs to be improved.
Core Tip: Endoscopy-based Kyoto classification of gastritis assesses gastric cancer (GC) risk and Helicobacter pylori (H. pylori) infection status. Total Kyoto scores of 0, ≥ 2, and ≥ 4 indicate a normal stomach, H. pylori-infected gastritis, and gastritis at risk for GC, respectively. Atrophy, intestinal metaplasia (IM), and enlarged folds (EF) increase H. pylori-infected GC incidence. Map-like redness is a specific risk factor for H. pylori-eradicated GC, while regular arrangement of collecting venules result in less GC risk. Diffuse-type GC is induced by active inflammation, depicting EF, nodularity, and atrophy. Intestinal-type GC develops through atrophy and IM; however, the GC risk-scoring design still needs to be improved.
