Prospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 28, 2015; 21(16): 5002-5008
Published online Apr 28, 2015. doi: 10.3748/wjg.v21.i16.5002
In vivo gastric mucosal histopathology using endocytoscopy
Hiroki Sato, Haruhiro Inoue, Haruo Ikeda, Chiaki Sato, Chainarong Phlanusittepha, Bu’Hussain Hayee, Esperanza Grace R Santi, Yasutoshi Kobayashi, Shin-ei Kudo
Hiroki Sato, Haruhiro Inoue, Haruo Ikeda, Chiaki Sato, Chainarong Phlanusittepha, Shin-ei Kudo, Digestive Disease Center, Showa University, Northern Yokohama Hospital, Yokohama 224-8503, Japan
Bu’Hussain Hayee, Department of Gastroenterology, King’s College Hospital NHS Foundation Trust, London SE5 9RS, United Kingdom
Esperanza Grace R Santi, Department of Gastroenterology, De La Salle University Medical Center, Dasmariñas City 4114, The Philippines
Yasutoshi Kobayashi, Kobayashi Internal Medicine Clinic, Kobe 652-0812, Japan
Author contributions: Sato H drafted the manuscript; Inoue H supervised the study; Ikeda H, Sato C and Phlanusittepha C contributed to technical support; Hayee B, Santi EGR and Kudo S contributed to critical revision of the manuscript; and Kobayashi Y contributed to statistical analysis.
Ethics approval: This study was reviewed and approved by the Showa University Northern Yokohama Hospital Institutional Review Board.
Clinical trial registration: This study was registered at
Informed consent: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest: There are no conflicts of interest.
Data sharing: No additional data are available.
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:
Correspondence to: Hiroki Sato, MD, PhD, Digestive Disease Center, Showa University, Northern Yokohama Hospital, 35-1 Chigasakichuo, Tsuzuki-ku, Yokohama 224-8503, Japan.
Telephone: +81-45-9497000 Fax: +81-45-9497000
Received: October 2, 2014
Peer-review started: October 4, 2014
First decision: October 29, 2014
Revised: November 7, 2014
Accepted: January 8, 2015
Article in press: January 8, 2015
Published online: April 28, 2015

AIM: To study the ability of endocytoscopy to identify normal gastric mucosa and to exclude Helicobacter pylori (H. pylori) infection.

METHODS: Endocytoscopic examination of the gastric corpus and antrum was performed in 70 consecutive patients. Target biopsy specimens were also obtained from the assessed region and multiple H. pylori tests were performed. The normal endocytoscopy patterns of the corpus and antrum were divided into the normal pit-dominant type (n-Pit) or the normal papilla-dominant type (n-Pap), respectively characterized as either regular pits with capillary networks or round, smooth papillary structures with spiral capillaries. On the other hand, normal mucosa was defined as mucosa not demonstrating histological abnormalities, including inflammation and atrophy.

RESULTS: The sensitivity and specificity of n-Pit for normal mucosa in the gastric corpus were 94.4% and 97.1%, respectively, whereas those of n-Pap for normal mucosa in the antrum were 92.0% and 86.7%, respectively. The positive predictive values of n-Pit and n-Pap for H. pylori-negative tissue were 88.6% and 93.1%, respectively, and their negative predictive values for H. pylori-negative tissues were 42.9% and 41.5%, respectively. The inter-observer agreement for determining n-Pit and n-Pap for normal mucosa were 0.857 and 0.769, respectively, which is considered reliable.

CONCLUSION: N-Pit and n-Pap, seen using EC, are considered useful predictors of normal mucosa and the absence of H. pylori infection.

Keywords: Atrophy, Endocytoscopy, Gastric mucosa, Helicobacter pylori, In vivo histopathology

Core tip: The identification of minute inflammatory or atrophic changes is very difficult using conventional endoscopy. This is because these changes are usually predicted using non-specific endoscopic findings, such as superficial color, edema and erosions. However, endocytoscopy enables real-time histology, which corresponds well with conventional histopathology. The procedure is also simple (the endocytoscope only has to make contact with the gastric wall) and is therefore expected to be used regularly globally in the future.