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Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Mar 15, 2016; 8(3): 271-281
Published online Mar 15, 2016. doi: 10.4251/wjgo.v8.i3.271
Gastric cancer development after the successful eradication of Helicobacter pylori
Kaname Uno, Katsunori Iijima, Tooru Shimosegawa
Kaname Uno, Katsunori Iijima, Tooru Shimosegawa, Division of Gastroenterology, Tohoku University Hospital, Miyagi 981-8574, Japan
Author contributions: All the authors contributed to the paper.
Conflict-of-interest statement: The authors declare no conflicts of interest regarding this manuscript.
Open-Access: 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/
Correspondence to: Kaname Uno, MD, PhD, Division of Gastroenterology, Tohoku University Hospital, 1-1 Seiryo-cho, Aoba-ku, Sendai, Miyagi 981-8574, Japan. kaname@wa2.so-net.ne.jp
Telephone: +81-22-7177171 Fax: +81-22-7177174
Received: June 5, 2015
Peer-review started: June 8, 2015
First decision: August 7, 2015
Revised: September 11, 2015
Accepted: December 13, 2015
Article in press: December 15, 2015
Published online: March 15, 2016
Processing time: 275 Days and 21.2 Hours
Abstract

Gastric cancer (GC) develops as a result of inflammation-associated carcinogenesis due to Helicobacter pylori (H. pylori) infection and subsequent defects in genetic/epigenetic events. Although the indication for eradication therapy has become widespread, clinical studies have revealed its limited effects in decreasing the incidence of GC. Moreover, research on biopsy specimens obtained by conventional endoscopy has demonstrated the feasibility of the restoration of some genetic/epigenetic alterations in the gastric mucosa. Practically, the number of sporadic cases of primary/metachronous GC that emerge after successful eradication has increased, while on-going guidelines recommend eradication therapy for patients with chronic gastritis and those with background mucosa after endoscopic resection for GC. Accordingly, regular surveillance of numerous individuals who have received eradication therapy is recommended despite the lack of biomarkers. Recently, the focus has been on functional reversibility after successful eradication as another cue to elucidate the mechanisms of restoration as well as those of carcinogenesis in the gastric mucosa after H. pylori eradication. We demonstrated that Congo-red chromoendoscopy enabled the identification of the multi-focal distribution of functionally irreversible mucosa compared with that of restored mucosa after successful eradication in individuals at extremely high risk for GC. Further research that uses functional imaging may provide new insights into the mechanisms of regeneration and carcinogenesis in the gastric mucosa post-eradication and may allow for the development of useful biomarkers.

Keywords: Helicobacter pylori eradication; Gastric cancer; Congo-red chromoendoscopy; Biomarker

Core tip: Since the indication for eradication therapy for Helicobacter pylori became widespread, the number of gastric cancer (GC) cases that emerge after eradication has continued to increase. However, the underlying mechanism of restoration/carcinogenesis in the gastric mucosa after eradication therapy has not been fully elucidated. We previously demonstrated that, instead of conventional endoscopy, Congo-red chromoendoscopy might be more precise in its ability to identify the multi-focal distribution of functionally irreversible mucosa that may be present in individuals with high risk for GC even after successful eradication. Further research using functional imaging may provide new insights to address the mechanism of gastric regeneration/carcinogenesis, and subsequently, may allow for the development of biomarkers for GC in high risk individuals during post-eradication surveillance.