Meta-Analysis
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2020; 26(15): 1820-1840
Published online Apr 21, 2020. doi: 10.3748/wjg.v26.i15.1820
Chemoprevention of gastric cancer development after Helicobacter pylori eradication therapy in an East Asian population: Meta-analysis
Mitsushige Sugimoto, Masaki Murata, Yoshio Yamaoka
Mitsushige Sugimoto, Department of Gastroenterological Endoscopy, Tokyo Medical University Hospital, Sinjuku, Tokyo 1600023, Japan
Masaki Murata, Department of Gastroenterology, National Hospital Organization Kyoto Medical Center, Kyoto 6128555, Japan
Yoshio Yamaoka, Department of Gastroenterology, Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita 8795593, Japan
Author contributions: Sugimoto M acquisition of data, analysis and interpretation of data, drafting the article, final approval; Murata M acquisition of data, analysis and interpretation of data, final approval; Yoshioka Y design of the study, final approval.
Conflict-of-interest statement: The authors deny any conflict of interest.
PRISMA 2009 Checklist statement: This study was conducted according to the PRISMA agreement reporting guidelines.
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Mitsushige Sugimoto, MD, PhD, AGAF, Professor, Department of Gastroenterological Endoscopy, Tokyo Medical University Hospital, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo 1600023, Japan. sugimo@tokyo-med.ac.jp
Received: December 16, 2019
Peer-review started: December 16, 2019
First decision: January 7, 2020
Revised: March 15, 2020
Accepted: April 1, 2020
Article in press: April 1, 2020
Published online: April 21, 2020
Processing time: 126 Days and 18.8 Hours
ARTICLE HIGHLIGHTS
Research background

Helicobacter pylori (H. pylori) infection is a risk factor for gastric cancer (GC), especially in East Asian populations. Most East Asian populations infected with H. pylori are at higher risk for GC than H. pylori-positive European and United States populations. H. pylori eradication therapy reduces GC risk in patients after endoscopic and operative resection for GC, as well as in patients with atrophic gastritis. However, it remains unclear whether eradication therapy exerts the same chemopreventive effect on GC among different groups, e.g., those of different nationalities, those with a history of gastritis alone, those with a prior history of GC resection, etc., with different risk levels for GC development.

Research motivation

We hope to up-date evidences for preventive effect on development of GC after eradication therapy in East Asian populations.

Research objectives

To clarify the preventive effects of H. pylori eradication therapy for development of GC in an East Asian population with a high incidence of GC.

Research methods

PubMed and the Cochrane Library were searched for randomized control trials (RCTs) and cohort studies published in English up to March 2019 using the terms “H. pylori,” “GC,” and “eradication therapy”. Subgroup analyses were conducted with regard to study designs (i.e., RCTs or cohort studies), country where the study was conducted (i.e., Japan, China, and South Korea), and observation periods (i.e., ≤ 5 years and > 5 years). The heterogeneity and publication bias were also measured.

Research results

For patients with atrophic gastritis alone and patients after resection for GC, 4 and 4 RCTs and 12 and 18 cohort studies were included, respectively. In RCTs, the median incidence of GC for the untreated control groups and the treatment groups in cases of gastritis alone was 272.7 (180.4–322.4) and 162.3 (72.5–588.2) per 100000 person-years. In RCTs, the median incidence of metachronous GC for the untreated control groups and the treatment groups was 1790.7 (406.5–2941.2) and 1126.2 (678.7–1223.1) per 100000 person-years. Compared with non-treated H. pylori-positive controls, the eradication groups had a significantly reduced risk of GC, with a relative risk of 0.67 [95% confidence interval: 0.47–0.96] for patients with atrophic gastritis alone and 0.51 (0.36–0.73) for patients after resection for GC in the RCTs and 0.39 (0.30–0.51) and 0.54 (0.44–0.67) in cohort studies.

Research conclusions

The current meta-analysis showed that in the East Asian population with high incidence rates of GC, H. pylori eradication effectively reduced the risk of GC, irrespective of past history of previous cancer. The surveillance interval in patients after endoscopic and operative resection and patients with atrophic gastritis alone is important after eradication therapy.

Research perspectives

The results of the current meta-analysis may offer gastroenterologists and endoscopists more reliable evidence in efficacy of H. pylori eradication therapy and importance of surveillance after eradication therapy.