Colorectal Endoscopic Submucosal Dissection

Is It Suitable in Western Countries?

Toshio Uraoka; Adolfo Parra-Blanco; Naohisa Yahagi

Disclosures

J Gastroenterol Hepatol. 2013;28(3):406-414. 

In This Article

Abstract and Introduction

Abstract

Endoscopic submucosal dissection (ESD) represents a significant advance in therapeutic endoscopy with the major advantage being the ability to achieve a higher en bloc resection rate for early stage lesions. Western endoscopists infrequently perform colorectal ESD (CR-ESD) because of the greater technical difficulty involved, longer procedure times, and increased risk of perforation. Specialized training and sufficient clinical experience are necessary to successfully perform ESDs, but a systematic education and training program has still not been established in Japan or elsewhere in the world. Experts generally acknowledge that the stomach is the first organ in which endoscopists should begin performing ESDs. The incidence and detection rates for early stage gastric cancer are significantly higher in Japan than in western countries, so Japanese endoscopists have a greater opportunity to perform gastric ESDs than their western counterparts. It is logical to ask, therefore, whether CR-ESD can be effectively applied in western countries. Based on a review of the relevant literature and our practical perspective, we have focused on the progress made in performing CR-ESD, its indications, training methods, and learning curve. Use of animal gastric and colon models is strongly recommended along with accumulating the necessary experience from the rectum to the colon on a step-by-step basis. It is reasonable to assume that an increasing number of CR-ESDs will be performed by western endoscopists in the foreseeable future given the continuing development of new techniques, and the refinement of instruments and other technologically advanced devices together with the creation of even more effective submucosal injection agents.

Introduction

Endoscopic mucosal resection (EMR) is widely accepted as a minimally invasive procedure for treating colorectal cancer (CRC) having a low risk of lymph node metastasis as well as colorectal adenomas.[1-3] Resection of large polyps can be performed en bloc or piecemeal depending on the size and location of a particular lesion. The perforation rate with EMR is relatively low, but large lesions ≥ 20 mm in diameter are technically more challenging.[4–6] As a result, the higher incidence of local recurrence after piecemeal EMR of such lesions is considered to be a serious problem.[7–10] The possibility of an incomplete resection also causes some concern in terms of inaccurate histopathological assessment, in addition to the increased risk of local recurrence. A surgical resection should be performed, therefore, in any case of unsatisfactory histopathological assessment of cancer invasion into the submucosal layer resulting from a multiple-piece resection.

Endoscopic submucosal dissection (ESD) was developed in Japan in the mid-1990s to resect early stage gastrointestinal tumors en bloc including large lesions and lesions evidencing a positive non-lifting sign.[11–23] ESD represents a significant advance in therapeutic endoscopy with a major advantage being the ability to achieve a higher en bloc resection rate by performing submucosal dissection using a special electrosurgical knife. This procedure has resulted in both more accurate histopathological assessment and enhanced curability.

ESD is not as widely performed in the colorectum compared with gastric ESD even in Japan, however, because of greater technical difficulty based on the anatomical features of the colon including its longer length, narrower lumen, extensive flexion and thinner walls, longer procedure time, and increased risk of perforation.[14–17,21–24] Despite these formidable challenges, the use of colorectal ESD (CR-ESD) has gradually been spreading largely because of the development and improvement of various endoscopic instruments and devices. In contrast to a growing number of Japanese and other East Asian endoscopists, however, western endoscopists infrequently perform CR-ESD despite its major advantages. Specialized training and adequate clinical experience therefore appear to be necessary in order to acquire a satisfactory level of skill for performing ESD.

This review article focuses on the progress made in performing CR-ESD and its indications, training methods, and learning curve based on applicable literature and our practical perspective with this highly effective procedure.

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