Optimal traction direction in traction-assisted gastric endoscopic submucosal dissection

Conventional Versus Traction-Assisted Endoscopic Submucosal Dissection for Esophageal, Gastric, and Colorectal Neoplasms: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Endoscopic submucosal dissection (ESD) is increasingly being utilized for the resection of superficial gastrointestinal neoplasms. However, the long procedure time poses a technical challenge for conventional ESD (C-ESD). Traction-assisted ESD (T-ESD) was developed to facilitate the procedure by reducing its duration. This study compares the efficacy and safety of C-ESD versus T-ESD in the treatment of esophageal, gastric, and colorectal neoplasms. Nine randomized controlled trials (RCTs) were analyzed. Traction-assisted ESD exhibited shorter mean dissection times for the esophagus and colorectal regions and lower perforation rates in colorectal cases. No significant differences were observed in en bloc resection or bleeding rates. Traction-assisted ESD proves to be more efficient in mean procedure time for esophageal and colorectal cases and safer in perforation rates for colorectal cases, but similar rates are noted for en bloc resection or bleeding.

Two traction methods that can facilitate esophageal endoscopic submucosal dissection

Different traction devices that can provide a visual field and attain appropriate tension at the dissection plane during endoscopic submucosal dissection (ESD) have been developed. Clip-with-line (CWL) is a classic traction device that can offer per-oral traction toward the direction where the line is drawn. A multicenter randomized controlled trial (CONNECT-E trial) comparing the conventional ESD and CWL-assisted ESD (CWL-ESD) for large esophageal tumors was conducted in Japan. This study showed that CWL-ESD was associated with a shorter procedure time (defined as the time from initiating submucosal injection to completing tumor removal) without increasing the risk of adverse events. Multivariate analysis revealed that whole-circumferential lesion and abdominal esophageal lesion were independent risk factors for technical difficulties, which were defined as a procedure time of > 120 min, perforation, piecemeal resection, inadvertent incision (any accidental incision caused by the electrosurgical knife within the marked area), or handover to another operator. Therefore, techniques other than CWL should be considered for these lesions. Several studies have shown the usefulness of endoscopic submucosal tunnel dissection (ESTD) for such lesions. A randomized controlled trial conducted at five Chinese institutions showed that compared with the conventional ESD, ESTD had a significantly reduced median procedure time for lesions covering ≥ 1/2 of the esophageal circumference. In addition, a propensity score matching analysis conducted at a single Chinese institution showed that compared with the conventional ESD, ESTD had a shorter mean resection time for lesions at the esophagogastric junction. With the appropriate use of CWL-ESD and ESTD, esophageal ESD can be performed more efficiently and safely. Moreover, the combination of these two methods may be effective.

Device-assisted traction methods in colorectal endoscopic submucosal dissection and options for difficult cases

Endoscopic submucosal dissection (ESD) procedure has a longer procedure time and higher perforation rate than endoscopic mucosal resection owing to technical complications, including a poor field of vision and inadequate tension for the submucosal dissection plane. Various traction devices were developed to secure the visual field and provide adequate tension for the dissection plane. Two randomized controlled trials demonstrated that traction devices reduce colorectal ESD procedure time compared with conventional ESD (C-ESD), but they had limitations, including a single-center fashion. The CONNECT-C trial was the first multicenter randomized controlled trial comparing the C-ESD and traction device-assisted ESD (T-ESD) for colorectal tumors. In the T-ESD, one of the device-assisted traction methods (S–O clip, clip-with-line, and clip pulley) was chosen according to the operator’s discretion. The median ESD procedure time (primary endpoint) was not significantly different between C-ESD and T-ESD. For lesions ≥ 30 mm in diameter or in cases treated by nonexpert operators, the median ESD procedure time tended to be shorter in T-ESD than in C-ESD. Although T-ESD did not reduce ESD procedure time, the CONNECT-C trial results suggest that T-ESD is effective for larger lesions and nonexpert operators in colorectal ESD. Compared with esophageal and gastric ESD, colorectal ESD has some difficulties, including poor endoscope maneuverability, which may be associated with prolonged ESD procedure time. T-ESD may not effectively improve these issues, but a balloon-assisted endoscope and underwater ESD may be promising options and these methods can be combined with T-ESD.

Impact of Traction Direction in Traction-Assisted Gastric Endoscopic Submucosal Dissection (with Videos)

BACKGROUND

The impact of traction direction in traction-assisted gastric endoscopic submucosal dissection (ESD) has not been adequately investigated. A clip with line (CWL) is a classical single-directional traction device. In contrast, a spring and loop with clip (SLC; S-O clip) is a newly developed multidirectional traction device.

AIMS

To investigate the impact of traction direction in gastric ESD by comparing the procedure-related outcomes of CWL-assisted ESD (CWL-ESD) and SLC-assisted ESD (SLC-ESD).

METHODS

We retrospectively examined 140 patients with superficial gastric neoplasms who underwent SLC-ESD or CWL-ESD by a single ESD expert during November 2017-September 2020. The traction direction was classified based on the endoscopic finding in the following five categories: proximal, diagonally proximal, vertical, diagonally distal, and distal. In SLC-ESD, we set vertical traction, using the multidirectional traction function. Propensity score matching was conducted to compensate for the differences in lesion size, injection function of electrosurgical knife, ulcerative lesion, lesion location, and lesion position. The primary outcome was gastric ESD procedure time.

RESULTS

Propensity score matching created 42 pairs. The median gastric ESD procedure time in the SLC-ESD group was significantly shorter than that in the CWL-ESD group (28.3 min vs. 51.0 min, P = 0.022). All traction direction in the SLC-ESD group was vertical, while only 16.7% in the CWL-ESD group. En bloc resection was attained without perforation in all the patients in both groups.

CONCLUSION

Our findings suggest that SLC can provide vertical traction, which reduces the gastric ESD procedure time. Multidirectional traction devices can provide vertical traction in most cases of gastric ESD, unlike single-directional traction devices. Vertical traction may reduce the gastric ESD procedure time.