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©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. Sep 10, 2015; 7(12): 1070-1077
Published online Sep 10, 2015. doi: 10.4253/wjge.v7.i12.1070
Diagnosis of small intramucosal signet ring cell carcinoma of the stomach by non-magnifying narrow-band imaging: A pilot study
Jiro Watari, Toshihiko Tomita, Hisatomo Ikehara, Masato Taki, Tomohiro Ogawa, Takahisa Yamasaki, Takashi Kondo, Fumihiko Toyoshima, Jun Sakurai, Tomoaki Kono, Katsuyuki Tozawa, Yoshio Ohda, Tadayuki Oshima, Hirokazu Fukui, Seiichi Hirota, Hiroto Miwa
Jiro Watari, Toshihiko Tomita, Hisatomo Ikehara, Masato Taki, Tomohiro Ogawa, Takahisa Yamasaki, Takashi Kondo, Fumihiko Toyoshima, Jun Sakurai, Tomoaki Kono, Katsuyuki Tozawa, Yoshio Ohda, Tadayuki Oshima, Hirokazu Fukui, Hiroto Miwa, Division of Gastroenterology, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan
Seiichi Hirota, Department of Surgical Pathology, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan
Author contributions: Watari J and Miwa H designed and performed the research study; Tomita T, Ikehara H, Taki M, Ogawa T, Yamasaki T, Kondo T, Toyoshima F, Sakurai J, Kono T, Tozawa K, Ohda Y, Oshima T and Fukui H helped to collect the data; Ogawa T performed the quantification of endoscopic findings; Hirota S diagnosed the histology; Watari J performed statistical analysis and wrote the paper.
Institutional review board statement: This study was approved by Institutional Review Board at Hyogo College of Medicine, Nishinomiya, Japan.
Informed consent statement: All patients in the study gave informed consent prior to endoscopy.
Conflict-of-interest statement: None.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at (watarij@hyo-med.ac.jp). Consent for data sharing was not obtained from the participants but the presented data are anonymized and risk of identification is low.
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: Jiro Watari, MD, PhD, Division of Gastroenterology, Department of Internal Medicine, Hyogo College of Medicine, 1-1, Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan. watarij@hyo-med.ac.jp
Telephone: +81-798-456662 Fax: +81-798-456661
Received: April 10, 2015
Peer-review started: April 12, 2015
First decision: June 4, 2015
Revised: July 22, 2015
Accepted: August 13, 2015
Article in press: August 26, 2015
Published online: September 10, 2015
AIM: To examine the efficacy of non-magnifying narrow-band imaging (NM-NBI) imaging for small signet ring cell carcinoma (SRC).
METHODS: We retrospectively analyzed 14 consecutive small intramucosal SRCs that had been treated with endoscopic submucosal dissection (ESD) and 14 randomly selected whitish gastric ulcer scars (control). The strength and shape of the SRCs and whitish scars by NM-NBI and white-light imaging (WLI) were assessed with Image J (NIH, Bethesda).
RESULTS: NM-NBI findings of SRC showed a clearly isolated whitish area amid the brown color of the surrounding normal mucosa. The NBI index, which indicates the potency of NBI for visualizing SRC, was significantly higher than the WLI index (P = 0.001), indicating SRC was more clearly identified by NM-NBI. Although the NBI index was not significantly different between SRCs and controls, the circle (C)-index, as an index of circularity of tumor shape, was significantly higher in SRCs (P = 0.001). According to the receiver-operating characteristic analysis, the resulting cut-off value of the circularity index (C-index) for SRC was 0.60 (85.7% sensitivity, 85.7% specificity). Thus a lesion with a C-index ≥ 0.6 was significantly more likely to be an SRC than a gastric ulcer scar (OR = 36.0; 95%CI: 4.33-299.09; P = 0.0009).
CONCLUSION: Small isolated whitish round area by NM-NBI endoscopy is a useful finding of SRCs which is the indication for ESD.
Core tip: Intramucosal signet ring cell carcinoma (SRC) ≤ 2 cm in diameter, for which endoscopic submucosal dissection is indicated, is very difficult to identify by white-light imaging (WLI) endoscopy. However, little is known regarding non-magnifying narrow-band imaging (NM-NBI) findings of early SRC. The strength and shape of the SRCs by NM-NBI and WLI were assessed with Image J. NM-NBI findings of SRC showed a clearly isolated whitish area amid the brown color of the surrounding normal mucosa. The NBI index, which indicates the potency of NBI for visualizing SRC, was significantly higher than the WLI index (P = 0.001).
