Retrospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2018; 24(15): 1632-1640
Published online Apr 21, 2018. doi: 10.3748/wjg.v24.i15.1632
Endoscopic submucosal dissection for early esophageal neoplasms using the stag beetle knife
Toshio Kuwai, Toshiki Yamaguchi, Hiroki Imagawa, Ryoichi Miura, Yuki Sumida, Takeshi Takasago, Yuki Miyasako, Tomoyuki Nishimura, Sumio Iio, Atsushi Yamaguchi, Hirotaka Kouno, Hiroshi Kohno, Sauid Ishaq
Toshio Kuwai, Toshiki Yamaguchi, Hiroki Imagawa, Ryoichi Miura, Yuki Sumida, Takeshi Takasago, Yuki Miyasako, Tomoyuki Nishimura, Sumio Iio, Atsushi Yamaguchi, Hirotaka Kouno, Hiroshi Kohno, Department of Gastroenterology, National Hospital Organization, Kure Medical Center and Chugoku Cancer Center, Kure 737-0023, Japan
Sauid Ishaq, Department of Gastroenterology, DGH, SGU, WI, Birmingham City University, Birmingham B4 7BD, United Kingdom
Author contributions: Kuwai T designed the research; Yamaguchi T, Imagawa H, Yamaguchi A, Kouno H, Kohno H and Ishaq S contributed by providing critical intellectual input for the revised manuscript; Kuwai T, Miura R, Sumida Y, Takasago T, Miyasako Y, Nishimura T and Iio S analyzed the data; Kuwai T wrote the article.
Institutional review board statement: This study was approved by the National Hospital Organization Kure Medical Center and the Chugoku Cancer Center Institutional Review Board Ethics Committee on 3 October 2016, the study incorporated good clinical practice, conforming to Declaration of Helsinki principles.
Informed consent statement: All patients were informed of the risks and benefits of ESD and provided written informed consent.
Conflict-of-interest statement: All authors declare no conflicts-of-interest related to this article.
Data sharing statement: 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: Toshio Kuwai, MD, PhD, Chief Doctor, Department of Gastroenterology, National Hospital Organization Kure Medical Center and Chugoku Cancer Center, 3-1 Aoyama-cho, Kure 737-0023, Japan.
Telephone: +81-823-223111 Fax: +81-823-210478
Received: February 9, 2018
Peer-review started: February 11, 2018
First decision: March 9, 2018
Revised: March 16, 2018
Accepted: March 31, 2018
Article in press: March 30, 2018
Published online: April 21, 2018
Research background

Several conventional endoscopic submucosal dissection (ESD) devices have been utilized for esophageal ESD. The thin wall with no serosa and narrow lumen of the esophageal wall make ESD more challenging in the esophagus. The restricted endoscopic maneuvering required with conventional ESD devices is also problematic owing to lack of fixation to targets and the fact that these devices are partially or entirely uninsulated. These factors can lead to unintentional incisions, increasing the potential risk of adverse events such as perforation and mediastinal emphysema.

Research motivation

The stag beetle (SB) knife, with its ability to grasp, assess, and then cut the targeted tissue allows endoscopists to maintain adequate dissection planes, preventing inadvertent injury to the muscular layer for safe ESD. Because of these advantages, the SB Knife is gaining acceptance, but relevant long-term outcome data is limited.

Research objectives

The aim of this study was to investigate use of the SB knife for ESD of early esophageal neoplasms, assessing both feasibility and safety. The subsequent short- and long-term clinical outcomes were examined as well.

Research methods

We retrospectively reviewed 70 consecutive patients with 96 early esophageal neoplasms (HGIN/SCC) treated using ESD. An SB knife was used routinely in all procedures. Clinicopathologic characteristics of the lesions and rates of procedural adverse events, en bloc and histologically complete resection, overall and tumor-specific survival, and local or distant recurrence were assessed.

Research results

The en bloc resection rate was 100%, with 95% and 81% of dissections deemed histologically complete and curative, respectively. All procedures were completed without accidental incisions/perforations or delayed bleeding. During follow-up (mean, 35 ± 23 mo), no local recurrences or metastases were observed. The 3- and 5-year survival rates were 83% and 70%, respectively. The 3- and 5-year cumulative rates of metachronous cancer in the patients with curative resections were 14% and 26%, respectively.

Research conclusions

ESD procedures using the SB knife are feasible, safe, and effective for treating early esophageal neoplasms, yielding favorable short- and long-term outcomes. No perforation occurred in our study population, attesting to the innovative design of the SB knife, which allows better control for safer dissection.

Research perspectives

The availability of this tool may promote widespread adoption of ESD to treat early-stage cancers of the esophagus. There is a need to conduct RCT studies to compare this new innovative device with established devices.