Randomized Clinical Trial
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2018; 24(35): 4077-4085
Published online Sep 21, 2018. doi: 10.3748/wjg.v24.i35.4077
Usefulness of the clip-flap method of endoscopic submucosal dissection: A randomized controlled trial
Hiromitsu Ban, Mitsushige Sugimoto, Taketo Otsuka, Masaki Murata, Toshiro Nakata, Hiroshi Hasegawa, Osamu Inatomi, Shigeki Bamba, Akira Andoh
Hiromitsu Ban, Mitsushige Sugimoto, Taketo Otsuka, Division of Digestive Endoscopy, Shiga University of Medical Science Hospital, Shiga 520-2192, Japan
Masaki Murata, Toshiro Nakata, Hiroshi Hasegawa, Osamu Inatomi, Akira Andoh, Department of Gastroenterology, Shiga University of Medical Science Hospital, Shiga 520-2192, Japan
Shigeki Bamba, Division of Clinical Nutrition, Shiga University of Medical Science Hospital, Shiga 520-2192, Japan
Author contributions: Ban H, Sugimoto M, Otsuka T, Murata M, Nakata T, Hasegawa H, Inatomi O, Bamba S and Andoh A designed this study; Ban H was the clinical investigator with more patients recruited and treated; Hasegawa H, Inatomi O, Bamba S and Andoh A, took part in trial coordination and monitoring; Ban H, Sugimoto M, Otsuka T, Murata M, Nakata T, Hasegawa H collected the data and their management; Ban H, Sugimoto M contributed to the statistical analysis; Ban H, Sugimoto M analyzed and interpreted the data; Ban H, Sugimoto M drafted the manuscript and made the final approval of the version to the published.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Shiga University of Medical Science.
Clinical trial registration statement: This study is registered on Universal hospital Medical Information Network (UMIN000018199).
Informed consent statement: All study participants provided written informed consent prior to study enrolment.
Conflict-of-interest statement: None of the authors have any conflicts of interest related to this study.
Data sharing statement: No additional data are available.
CONSORT 2010 statement: The CONSORT 2010 Statement have been adopted.
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: Mitsushige Sugimoto, MD, PhD, Associate Professor, Division of Digestive Endoscopy, Shiga University of Medical Science Hospital, Seta Tsukinowa-cho, Otsu, Shiga 520-2192, Japan. sugimo@belle.shiga-med.ac.jp
Telephone: +81-77-5482618 Fax: +81-77-5482618
Received: June 21, 2018
Peer-review started: June 21, 2018
First decision: July 31, 2018
Revised: August 5, 2018
Accepted: August 24, 2018
Article in press: August 24, 2018
Published online: September 21, 2018
Research background

The endoscopic submucosal dissection (ESD) for early-stage gastric cancer is first-line endoscopic therapy in Japan, because of en bloc resection and a lower local recurrence rate of gastric cancer. However, ESD often causes development of adverse events, such as gastric bleeding and perforation. When ESD is performed for gastric cancer, poor visualization in the resection area during ESD procedure results in longer procedure times and their associated development of above adverse events. Now, the gold standardized method for resection by ESD for all of patients with early-stage gastric cancer and adenoma has not been established in point of continuous clear visualization in the resection area.

Research motivation

To keep clear visualization at early-phase after starting ESD procedure, endoscopists are required to create a mucosal flap. Of several traction systems to create mucosal flap, recently, the clip-flap method is focused, because of safety and correctly compared with other methods. However, it is unknown whether the clip-flap method is appropriate for patients with early-stage gastric tumors.

Research objectives

The main objective was to investigate prospectively the efficacy (the rate of en bloc resection and procedure time of ESD) and safety (gastric bleeding and perforation) of clip-flap assisted ESD for gastric cancer and adenoma.

Research methods

We enrolled 104 patients with gastric cancer or adenoma scheduled for ESD. Inclusion criteria were age > 20 years and the diagnosis of gastric adenoma or clinical early-stage gastric cancer. Early-stage gastric cancers were clinically diagnosed using endoscopy, endoscopic ultrasonography, histopathology, and computed tomography. We randomized patients into two subgroups using the minimization method based on location of the tumor, tumor size and ulcer status: ESD using an endoclip (the clip-flap group) and ESD without an endoclip (the conventional group). Therapeutic efficacy and safety were assessed.

Research results

No significant differences in en bloc resection rate (P = 1.00), curative endoscopic resection rate (P = 0.85), procedure time (P = 0.69), area of resected specimen (P = 0.49), delayed bleeding rate (P = 0.49), or perforation rate (P = 0.93) were found between the clip-flap group and the conventional group.

Research conclusions

For patients with early-stage gastric cancer and adenoma, the clip-flap method has no advantage in efficacy or safety compared with the conventional method. Although operators scored superiority of the clip-flap method in 30% of ESD procedures, in 25% of cases the operators evaluated the clip-flap method as inferior, usually because the head of the endoclip interfered with the cutting edge, making ESD more difficult. Therefore, the best way to do this method is to property place the clip on the lesion.

Research perspectives

Although the clip-flap method has been proven to be advantageous for patients with early-stage colorectal tumors compared with the conventional method, the superiority of clip-flap method-assisted ESD in the stomach is unproven. When considering clip-flap-assisted ESD, endoscopists should select patients, especially cases in which it is difficult to ensure a fine visualization, and should apply the endoclip carefully so that the head of the endoclip pushes downward.