Comparison of hemostatic ability between spray coagulation and forced coagulation modes in endoscopic submucosal dissection in patients with early gastric neoplasms: a study protocol for multicenter randomized controlled trial (Spray-G trial).

BACKGROUND: Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric neoplasms (EGN). Controlling intraoperative bleeding is crucial for ensuring safe and reliable procedures. ESD using the spray coagulation mode (SCM-ESD) has been developed to control bleeding more effectively than ESD using the conventional forced coagulation mode (FCM-ESD). This study aims to compare the hemostatic efficacies of SCM-ESD and FCM-ESD. METHODS: This multicenter, prospective, parallel, randomized, open-label superiority trial will be conducted in five Japanese institutions. Patients with a preoperative diagnosis of intramucosal EGC will be randomized to undergo either SCM-ESD or FCM-ESD. The primary outcome measure is the completion of ESD with an electrosurgical knife alone, without the use of hemostatic forceps. Secondary outcomes include the number and duration of hemostasis using hemostatic forceps, procedure time, curability, and safety. A total of 130 patients will be enrolled in this study. DISCUSSION: This trial will provide evidence on the hemostatic efficacy of SCM-ESD compared with FCM-ESD in patients with intramucosal EGN, potentially improving the safety and reliability of ESD procedures. TRIAL REGISTRATION: The trial has been registered at the University Hospital Medical Information Network Clinical Trials Registration (UMIN-CTR) as UMIN000040518. The reception number is R000054009.

Efficacy of hybrid endoscopic submucosal dissection with SOUTEN in gastric lesions: An ex vivo porcine model basic study.

BACKGROUND: Hybrid endoscopic submucosal dissection (ESD) that comprises mucosal incision and partial submucosal dissection followed by snaring in a planned manner, has been developed for endoscopic resection of gastrointestinal neoplasms to overcome the technical barrier of ESD. Although the superiority of hybrid ESD with SOUTEN, a single multifunctional device, over conventional ESD has been indicated, the actual effect of snaring itself remains unclear since SOUTEN could be applied to hybrid ESD group, but not to the conventional ESD group, due to ethical issue in clinical practice. AIM: To determine whether and how hybrid ESD was superior to conventional ESD in the endoscopic treatment of gastric lesions in an ex vivo porcine model basic study. METHODS: Sixteen endoscopists participated in this basic study in August 2020 at Kyushu University, performing 32 procedures each for hybrid ESD and conventional ESD. Mock lesions (10-15 mm, diameter) were created in the porcine stomach. The primary outcome was total procedure time and secondary outcomes were en bloc or complete resection, perforation, procedure time/speed for both, mucosal incision, and submucosal dissection. Factors associated with difficulty in ESD including longer procedure time, incomplete resection, and perforation, were also investigated. Categorical and continuous data were analyzed using the chi-square test or Fisher's exact test and the Mann-Whitney U test, respectively. RESULTS: The median total procedure time of hybrid ESD was significantly shorter than that of conventional ESD (median: 8.3 min vs 16.2 min, P < 0.001). Time, speed, and the amount of hyaluronic acid during submucosal dissection were more favorable in hybrid ESD than conventional ESD (time, 5.2 min vs 10.4 min, P < 0.001; speed, 43.7 mm2/min vs 23.8 mm2/min, P < 0.00; injection volume, 1.5 mL vs 3.0 mL, P < 0.001), although no significant differences in those factors were observed between both groups during mucosal incision. There was also no significant difference between both groups in the en bloc/complete resection rate and perforation rate (complete resection, 93.8% vs 87.5%, P = 0.67; perforation, 0% vs 3.1%, P = 1). Selection of conventional ESD as the treatment method was significantly associated with difficulties during ESD (odds ratio = 10.2; highest among factors). CONCLUSION: Hybrid ESD with SOUTEN improves the treatment outcomes of gastric lesions. It also has the potential to reduce medical costs since SOUTEN is a single multifunctional device that is inexpensive.

The Efficacy and Safety of a Promising Single-Channel Endoscopic Closure Technique for Endoscopic Treatment-Related Artificial Ulcers: A Pilot Study.

BACKGROUND/AIMS: It is important to appropriately manage patients with procedure-related artificial mucosal ulcers or procedure-related complications. Many endoscopic closure techniques have been reported; however, they often require the use of special devices. We developed a single-channel endoscopic closure technique (SCCT) that can be performed with conventional devices. In the present study, we describe the technique and evaluate its efficacy. METHODS: Twenty-five consecutive patients who underwent endoscopic treatment and whose artificial ulcer was closed using the SCCT were enrolled in this study. The technical success rate, number of clips for closure, procedure time, complication rate on the day of the procedure, clinical success rates on days 1 and 5, and incidence of severe stenosis of the gastrointestinal (GI) tract at 2 months after the procedure were evaluated. RESULTS: The median ulcer diameter was 20 mm. The tumor locations were the stomach (n = 19), jejunum (n = 1), and colon (n = 5). The technical success rate was 100% (25/25), and the rate of incomplete closure was 0% (0/25). Eight clips were needed on average. The median procedure time was 18 min (range 5-49 min). The complication rate was 0% (25/25). The clinical success rates on days 1 and 5 were 100% (19/19) and 100% (9/9), respectively. No patients presented stenosis as a late complication at 2 months after the procedure (0/25). CONCLUSION: The SCCT could be applied in the treatment of artificial ulcers in several parts of the GI tract with a high clinical success rate and no complications. The SCCT appears to be a good option for closing artificial mucosal ulcers.

Long-term inhibition of RhoA attenuates vascular contractility by enhancing endothelial NO production in an intact rabbit mesenteric artery.

RhoA plays a critical role in regulating NO production in cultured endothelial cells. To determine its role in in situ endothelial cells, we investigated the effects of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitors and a RhoA-binding domain of Rho-kinase (RB) on vascular contractility in the isolated rabbit mesenteric artery. Ex vivo treatment of the strips with 3x10(-5) mol/L simvastatin and fluvastatin for approximately 24 to 30 hours significantly attenuated the contractile response to phenylephrine and high K+ in the presence of endothelium. The addition of N(omega)-nitro-L-arginine methyl ester and the removal of endothelium abolished the attenuation of the contractile response. The cotreatment with geranylgeranyl pyrophosphate prevented the statin-induced attenuation of the contractile response, whereas geranylgeranyl transferase inhibitor mimicked the effect of simvastatin. Treatment with simvastatin enhanced the bradykinin-induced endothelium-dependent relaxation in the mesenteric artery, whereas it had no effect on the bradykinin-induced [Ca2+]i elevation in endothelial cells of the aortic valves. Introduction of RB to the strips using a cell-penetrating peptide of Tat protein (TATHA-RB) attenuated the contractile responses in a NO-dependent manner. However, a Rac1/Cdc42-binding fragment of p21-activated protein kinase, RB without Tat peptide or TATHA-protein A had no effect. The in vivo treatment of rabbit with simvastatin and TATHA-RB attenuated the contractility in a NO-dependent manner. Simvastatin and TATHA-RB significantly upregulated eNOS in the rabbit mesenteric artery. The present study provides the first evidence that RhoA plays a physiological role in suppressing NO production in in situ endothelial cells.