Self-Completion Method of Endoscopic Submucosal Dissection Using Endosaber without Any Other Device or Assistance: An ex vivo Porcine Model Study.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a standard treatment for tumors of the gastrointestinal tract. We developed a self-completion method of ESD using Endosaber to eliminate the need for an additional device or human assistance during the procedure. The aim of this study was to evaluate the technical feasibility and outcomes of this method in an ex vivo porcine training model. METHODS: This was a pilot study, and the procedures were performed by 4 experts. Mock lesions measuring 15 mm in diameter were prepared at the posterior wall in the middle or lower esophagus obtained from domestic pigs. Each operator performed ESD on the mock lesions in 3 models. The primary outcome was ESD completion rate using the self-completion method. The secondary outcomes were procedure time, en bloc resection rate, perforation rate, and number of injections during the procedure. RESULTS: All 12 ESDs were completed using the self-completion method. The median procedure time (interquartile range) was 483.5 (399-619.3) s (median incision time: 240.4 [168.3-332.5] s; median dissection time: 222 [182.8-257] s). En bloc resection rate was 100%. No perforation was noted during any of the procedures. The median number of injections was 10.5 (9-14.3). The procedure time decreased significantly with increase in experience (p = 0.020). CONCLUSIONS: The self-completion ESD method using one Endosaber without any assistance achieved a 100% en bloc resection rate without any perforation. The need for an additional device or assistance was successfully eliminated. This method may prove to be a simple and cost-effective ESD procedure for lesions in humans.

Assistant skill in gastric endoscopic submucosal dissection using a clutch cutter.

BACKGROUND: A clutch cutter is a scissor-type knife used in endoscopic submucosal dissection (ESD) for gastrointestinal tract tumors. The assistant during the ESD using a clutch cutter (ESD-C) needs to rotate the device and grasp the target tissue appropriately; therefore, the assistant's skill may affect the technical outcomes of ESD-C. AIM: To determine how assistant skill level affected the technical outcomes of gastric ESD-C using an ex vivo porcine training model. METHODS: In this pilot study, mock lesions of 15-30 mm in diameter were created in the middle or lower third of the porcine stomach. A total of 32 ESD-C procedures were performed by 16 trainees. Each trainee operator performed two ESD-C procedures; one ESD-C was assisted by an expert (ESD-C-E), and the other was assisted by a non-expert (ESD-C-NE). The total procedure time of the ESD was set as the primary outcome, and en bloc resection rate, complete procedure rate, perforation rate, and each procedure time/speed for mucosal incision or submucosal dissection were set as the secondary outcomes. In addition, we investigated factors associated with the difficulty of ESD including incompletion of ESD procedure, a long procedure time (≥ 20 min) or intraoperative perforation. RESULTS: The median total procedure time of the ESD-C-E was significantly shorter than that of the ESD-C-NE (12.9 min vs 21.9 min, P = 0.001). The en bloc resection rate was 100% in both groups. Complete resection rates of the ESD-C-E and ESD-C-NE groups were 100% and 93.8%, respectively. No intraoperative perforation was observed in both groups. In the multivariate analysis, assistant skill was significantly associated with the difficulty of ESD, with the highest odds ratio of 16.5. CONCLUSION: Assistance by an expert is an important factor when trainees perform ESD-C procedures.

Efficacy of traction, using a clip-with-thread, for esophageal endoscopic submucosal dissection for esophageal lesions with fibrosis in an ex vivo pig training model.

BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) of recurrent esophageal carcinoma is technically difficult to perform due to submucosal fibrosis that develops after definitive chemoradiation therapy. Therefore, our aim was to evaluate the usefulness of clip-with-thread traction for ESD of esophageal lesions with submucosal fibrosis. MATERIALS AND METHODS: Four endoscopists excised 16 lesions by ESD in an ex vivo pig training model. Mock lesions (30 mm in diameter) were created, including a 10-mm area of submucosal fibrosis in the center of each lesion. Each endoscopist performed two ESDs with traction (ESD-T) and two without traction (ESD-N). The primary outcome was the time required for submucosal dissection. Secondary outcomes were the rate of en bloc (complete) resection and perforation during the procedure, and the total amount of solution injected. RESULTS: All esophageal ESDs were completed. The median dissection time was significantly shorter for the ESD-T group (median 12.5 min, interquartile range 10.2-14.5) when comparing to the ESD-N group (median 18.0 min, interquartile range 14.6-19.2) (P=0.040). The en bloc resection rate was 100% in both groups, with a rate of complete resection of 87.5% and a rate of perforation of 37.5% for both groups. The median amount of solution injected was not significantly different between the ESD-T (18.0 ml) and ESD-N (20.5 ml) groups (P=0.526). CONCLUSION: Clip-with-thread traction improved the performance of ESD for lesions with submucosal fibrosis. However, the method might not reduce the risk of perforation, which remains an important clinical issue to resolve.

Clutch Cutter knife efficacy in endoscopic submucosal dissection for early gastric neoplasms.

AIM: To compare the outcomes of endoscopic submucosal dissection (ESD) for gastric neoplasms using Clutch Cutter (ESD-C) or other knives (ESD-O). METHODS: This was a single-center retrospective study. Gastric neoplasms treated by ESD between April 2016 and October 2017 at Kitakyushu Municipal Medical Center were reviewed. Multivariate analyses and propensity score matching were used to reduce biases. Covariates included factors that might affect outcomes of ESD, including age, sex, underlying disease, anti-thrombotic drugs use, tumor location, tumor position, tumor size, tumor depth, tumor morphology, tumor histology, ulcer (scar), and operator skill. The treatment outcomes were compared among two groups. The primary outcome was ESD procedure time. Secondary outcomes were en bloc, complete, and curative resection rates, and adverse events rates including perforation and delayed bleeding. RESULTS: A total of 155 patients were included in this study; 44 pairs were created by propensity score matching. Background characteristics were quite similar among two groups after matching. Procedure time was significantly shorter for ESD-C (median; 49 min) than for ESD-O (median; 88.5 min) (P < 0.01). However, there was no significant difference in treatment outcomes between ESD-C and ESD-O including en bloc resection rate (100% in both groups), complete resection rate (100% in both groups), curative resection rate (86.4% vs 88.6%, P = 0.730), delayed bleeding (2.3% vs 6.8%, P = 0.62) and perforation (0% in both groups). CONCLUSION: ESD-C achieved shorter procedure time without an increase in complication risk. Therefore, ESD-C could become an effective ESD option for gastric neoplasms.