Observational Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 21, 2015; 21(27): 8408-8417
Published online Jul 21, 2015. doi: 10.3748/wjg.v21.i27.8408
Gastric mucosa in Mongolian and Japanese patients with gastric cancer and Helicobacter pylori infection
Takeshi Matsuhisa, Yoshio Yamaoka, Tomohisa Uchida, Davaadorj Duger, Battulga Adiyasuren, Oyuntsetseg Khasag, Tserentogtokh Tegshee, Byambajav Tsogt-Ochir
Takeshi Matsuhisa, Department of Gastroenterology, Tama-Nagayama University Hospital, Nippon Medical School, Tokyo 206-8512, Japan
Yoshio Yamaoka, Department of Environmental and Preventive Medicine, Oita University of Medicine, Oita 879-5593, Japan
Tomohisa Uchida, Department of Molecular Pathology, Oita University of Medicine, Oita 879-5593, Japan
Davaadorj Duger, Vice President of Mongolian National University of Medical Sciences and President of Mongolian Society of Gastroenterology, Ulaanbaatar 14210, Mongolia
Battulga Adiyasuren, Department of Endoscopy, Ulaanbaatar Songdo Hospital, Ulaanbaatar 14210, Mongolia
Oyuntsetseg Khasag, Byambajav Tsogt-Ochir, Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar 14210, Mongolia
Tserentogtokh Tegshee, Department of Gastroenterology, Third Central State Hospital, Ulaanbaatar 16081, Mongolia
Author contributions: Matsuhisa T and Yamaoka Y contributed to study conception and design, data interpretation, and writing, editing, review, and approval of the article; Matsuhisa T, Yamaoka Y, Uchida T, Duger D, Adiyasuren B, Khasag O, Tegshee T and Tsogt-Ochir B contributed to data acquisition.
Supported by (in part) National Institutes of Health, No. DK62813; and Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, No. 24406015, No. 24659200, No. 25293104, and No. 26640114.
Institutional review board statement: This study was reviewed and approved by the ethics committees of Nippon Medical School, Tokyo, Japan; Oita University, Oita, Japan; Mongolian National University of Medical Sciences, Ulaanbaatar, Mongolia; Ulaanbaatar Songdo Hospital, Ulaanbaatar, Mongolia; and Third Central State Hospital, Ulaanbaatar, Mongolia.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: Matsuhisa T has received research funding from Eisai Co., Ltd as a part of this study.
Data sharing statement: The technical appendix, statistical code, and dataset are available from the corresponding author at matuhisa@nms.ac.jp.
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: Takeshi Matsuhisa, MD, Professor, Department of Gastroenterology, Tama-Nagayama University Hospital, Nippon Medical School, Tama, Tokyo 206-8512, Japan. matuhisa@nms.ac.jp
Telephone: +81-42-3712111 Fax: +81-42-3727381
Received: January 24, 2015
Peer-review started: January 25, 2015
First decision: March 10, 2015
Revised: March 30, 2015
Accepted: May 21, 2015
Article in press: May 21, 2015
Published online: July 21, 2015
Processing time: 179 Days and 3 Hours
Core Tip

Core tip: Characteristics of gastric cancer and gastric mucosa in Mongolian patients were observed; approximately half of the cancers were located in the upper part of the stomach. The infection rate of Helicobacter pylori was higher in Mongolian compared to Japanese patients (75.9% vs 48.3%, P < 0.0001). Mongolian patients were infected with non-East-Asian-type H. pylori strains. Atrophic and intestinal metaplasia scores were lower in H. pylori-infected Mongolian patients compared to Japanese patients (P < 0.0001). The type of gastritis changed from antrum-predominant gastritis to corpus-predominant gastritis with age in both populations.