Case Report
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jun 15, 2017; 9(6): 263-267
Published online Jun 15, 2017. doi: 10.4251/wjgo.v9.i6.263
Gastric plexiform fibromyxoma resected by endoscopic submucosal dissection after observation of chronological changes: A case report
Fumiaki Kawara, Shinwa Tanaka, Takashi Yamasaki, Yoshinori Morita, Yoshiko Ohara, Yoshihiro Okabe, Namiko Hoshi, Takashi Toyonaga, Eiji Umegaki, Hiroshi Yokozaki, Takanori Hirose, Takeshi Azuma
Fumiaki Kawara, Shinwa Tanaka, Yoshinori Morita, Yoshiko Ohara, Yoshihiro Okabe, Namiko Hoshi, Takashi Toyonaga, Eiji Umegaki, Takeshi Azuma, Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
Takashi Yamasaki, Hiroshi Yokozaki, Division of Pathology, Department of Pathology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
Takanori Hirose, Department of Diagnostic Pathology, Hyogo Cancer Center, Akashi 673-8558, Japan
Author contributions: Kawara F, Tanaka S and Morita Y performed endoscopic resection and wrote the manuscript; Kawara F, Ohara Y and Okabe Y performed follow-up endoscopy and endoscopic ultrasound; Yamasaki T, Yokozaki H and Hirose T performed histopathological examinations; Hoshi N, Toyonaga T, Umegaki E and Azuma T contributed to the literature review and manuscript editing.
Institutional review board statement: This case report was exempt from approval by the Ethics Committee of Kobe University Hospital.
Informed consent statement: Informed consent was obtained from the patient.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest.
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: Fumiaki Kawara, MD, PhD, Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan. lankey11@med.kobe-u.ac.jp
Telephone: +81-78-3826305 Fax: +81-78-3826309
Received: October 23, 2016
Peer-review started: October 25, 2016
First decision: March 8, 2017
Revised: March 22, 2017
Accepted: May 3, 2017
Article in press: May 5, 2017
Published online: June 15, 2017
Abstract

A 66-year-old man was diagnosed with a gastric submucosal tumor. Endoscopic ultrasound (EUS) revealed an iso/hypoechoic mass in the third layer. No malignant cells were detected in a histological examination. Yearly follow-up endoscopy and EUS showed the slow growth of the tumor. Endoscopic submucosal dissection (ESD) was performed and a glistening tumor was resected. The lesion showed a multinodular plexiform growth pattern consisting of spindle cells with an abundant fibromyxoid stroma that was rich in small vessels. The tumor was diagnosed as plexiform fibromyxoma (PF) by immunohistochemistry. Although difficulties are associated with reaching a diagnosis preoperatively, chronological changes on EUS may contribute to the diagnosis of PF. ESD may also be useful in the diagnosis and treatment of PF.

Keywords: Plexiform fibromyxoma, Plexiform angiomyxoid myofibroblastic tumor, Endoscopic ultrasound, Endoscopic submucosal dissection, Gastrointestinal stromal tumor

Core tip: Plexiform fibromyxoma (PF) is a very rare gastric submucosal tumor. Therefore, difficulties are associated with diagnosing PF preoperatively, particularly in a differential diagnosis of gastrointestinal stromal tumors with cystic changes. We suggest that the chronological changes observed by endoscopic ultrasound contribute to the preoperative diagnosis of PF. Furthermore, endoscopic submucosal dissection needs to be considered for the diagnostic treatment of PF without muscle invasion.