Gel Immersion Endoscopic Submucosal Dissection Using a Scissor-type Knife for Superficial Non-ampullary Duodenal Epithelial Tumors

Objectives

This study aimed to compare the short-term therapeutic outcomes between conventional endoscopic submucosal dissection (C-ESD) and gel immersion ESD (GI-ESD) for superficial non-ampullary duodenal epithelial tumors (SNADETs).

Methods

A retrospective analysis was conducted on patients with SNADETs who underwent C-ESD or GI-ESD between June 2016 and May 2024. To reduce proficiency bias, the first 50 cases per endoscopist were excluded. C-ESD was performed using a scissor-type knife under CO₂ insufflation, while GI-ESD was performed using the same knife under gel immersion. Primary outcomes included en bloc and R0 resection rates; secondary outcomes were resection time, adverse events, and inflammatory response.

Results

Overall, 51 C-ESD and 49 GI-ESD procedures were analyzed. Both groups achieved 100% en bloc resection. R0 resection rates were comparable (C-ESD: 92.6%, GI-ESD: 90.2%, p = 0.661). Muscle layer exposure was significantly lower in the GI-ESD group (1.9%) than in the C-ESD group (16.7%, p = 0.032). The mean white blood cell count was also significantly lower in the GI-ESD group (p = 0.038). The incidence of adverse events in the C-ESD and GI-ESD groups was 5.6% and 1.9%, respectively (p = 0.627). However, no cases of perforation or aspiration were observed in the GI-ESD group.

Conclusions

GI-ESD is a safe and effective alternative to conventional ESD for SNADETs, offering comparable resection outcomes and low risk of adverse events with a reduced risk of muscle layer exposure.