Hybrid and Conventional Endoscopic Submucosal Dissection for Early Gastric Neoplasms: A Multi-Center Randomized Controlled Trial.

BACKGROUND & AIMS: Hybrid endoscopic submucosal dissection (H-ESD), which incorporates endoscopic submucosal dissection (ESD) with endoscopic mucosal resection, has been developed to make ESD technically easier. This study aimed to determine if H-ESD is superior to conventional ESD (C-ESD) for small early gastric neoplasms (EGNs). METHODS: We conducted a multi-center, prospective, open-label, randomized controlled trial to compare the treatment outcomes of H-ESD and C-ESD (Hybrid-G Trial). Patients with differentiated type intramucosal EGN ≤20 mm in diameter and without ulceration were randomly assigned (1:1) to groups that underwent H-ESD or C-ESD. A single multi-functional snare, SOUTEN (ST1850-20, Kaneka, Medix, Tokyo, Japan), was used for H-ESD. The primary outcome was procedure time. Secondary outcomes included mucosal incision time, time and speed of submucosal dissection, curability, and endoscopic procedural adverse events. RESULTS: A total of 39 and 40 patients underwent H-ESD and C-ESD, respectively. The procedure time of H-ESD was significantly shorter than that of C-ESD (33.16 min vs 62.46 min; H-ESD/C-ESD ratio: 0.53; 95% confidence interval, 0.41-0.69; P < .0001). There was no significant difference in mucosal incision time between the 2 groups; the time and speed of submucosal dissection of H-ESD were significantly shorter than those of C-ESD. No difference was observed between the 2 groups in other outcomes. CONCLUSIONS: H-ESD has significantly shorter procedure time than C-ESD, with high and comparable curability and safety for both H-ESD and C-ESD. H-ESD can be a good option for the endoscopic treatment of small EGNs. (UMIN Clinical Trials Registry, Numbers: UMIN000041244).

Auxiliary diagnosis of subepithelial lesions by impedance measurement during EUS-guided fine-needle biopsy.

BACKGROUND AND AIMS: EUS-guided FNA/biopsy (EUS-FNA/B) is the citerion standard for diagnosing subepithelial lesions (SELs); however, its diagnostic ability for SELs <20 mm is low. We developed a new diagnostic method to differentiate between GI stromal tumor (GIST) and non-GIST by measuring high-frequency impedance (H-impedance) using an EUS-FNB needle. METHODS: The H-impedance of gastric epithelial neoplasms from 16 cases were measured with a conventional impedance probe to confirm whether H-impedance is clinically useful for assessing cell density (study 1). The H-impedance values of exposed SELs from 25 cases with use of the conventional probe (study 2) and nonexposed SELs from 20 cases with use of the EUS-FNB needle probe (study 3) were measured to determine the diagnostic ability of H-impedance for differentiating GISTs from non-GISTs. RESULTS: H-impedance significantly positively correlated with cell density (P = .030) (study 1). The H-impedance of GIST (99.5) measured with a conventional probe was significantly higher than with those of the muscular layer (82.4) and leiomyoma (89.2) (P < .01) (study 2). The H-impedance of GIST measured with the EUS-FNB needle was also significantly higher than that of leiomyoma (GIST: 80.2 vs leiomyoma, 71.8; P = .015). The diagnostic yield of the impedance method for differentiating GISTs from non-GISTs had 94.4% accuracy, 88.9% sensitivity, 100% specificity, and 0.95 area under the curve. Diagnostic ability was not affected by lesion size (P = .86) (study 3). CONCLUSION: Auxiliary differential diagnosis between gastric GISTs and non-GISTs by the H-impedance measurement during EUS-FNB could be a good option, especially when the lesion is <20 mm.

Determination of Region-Specific Roles of the M3 Muscarinic Acetylcholine Receptor in Gastrointestinal Motility.

BACKGROUND: The specific role of the M3 muscarinic acetylcholine receptor in gastrointestinal motility under physiological conditions is unclear, due to a lack of subtype-selective compounds. AIMS: The objective of this study was to determine the region-specific role of the M3 receptor in gastrointestinal motility. METHODS: We developed a novel positive allosteric modulator (PAM) for the M3 receptor, PAM-369. The effects of PAM-369 on the carbachol-induced contractile response of porcine esophageal smooth muscle and mouse colonic smooth muscle (ex vivo) and on the transit in mouse small intestine and rat colon (in vivo) were examined. RESULTS: PAM-369 selectively potentiated the M3 receptor under the stimulation of its orthosteric ligands without agonistic or antagonistic activity. Half-maximal effective concentrations of PAM activity for human, mouse, and rat M3 receptors were 0.253, 0.345, and 0.127 µM, respectively. PAM-369 enhanced carbachol-induced contraction in porcine esophageal smooth muscle and mouse colonic smooth muscle without causing any contractile responses by itself. The oral administration of 30 mg/kg PAM-369 increased the small intestinal transit in both normal motility and loperamide-induced intestinal dysmotility mice but had no effects on the colonic transit, although the M3 receptor mRNA expression is higher in the colon than in the small intestine. CONCLUSIONS: This study provided the first direct evidence that the M3 receptor has different region-specific roles in the motility function between the small intestine and colon in physiological and pathophysiological contexts. Selective PAMs designed for targeted subtypes of muscarinic receptors are useful for elucidating the subtype-specific function.

Negligible procedure-related dissemination risk of mucosal incision-assisted biopsy for gastrointestinal stromal tumors versus endoscopic ultrasound-guided fine-needle aspiration/biopsy.

BACKGROUND: Mucosal incision-assisted biopsy (MIAB) is a valuable alternative to endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNAB) for sampling gastric subepithelial lesions (SELs). This study aimed to evaluate the potential risk of dissemination and impact on postoperative prognosis associated with MIAB, which has not yet been investigated. METHODS: Study 1: A prospective observational study was conducted to examine the presence or absence and growth rate of tumor cells in gastric juice before and after the procedure in patients with SELs who underwent MIAB (n = 25) or EUS-FNAB (n = 22) between September 2018 and August 2021. Study 2: A retrospective study was conducted to examine the impact of MIAB on postoperative prognosis in 107 patients with gastrointestinal stromal tumors diagnosed using MIAB (n = 39) or EUS-FNAB (n = 68) who underwent surgery between January 2001 and July 2020. RESULTS: In study 1, although no tumor cells were observed in gastric juice in MIAB before the procedure, they were observed in 64% of patients after obtaining samples (P < 0.001). In contrast, no tumor cells were observed in the gastric juice in EUS-FNAB before and after the procedure. In study 2, there was no significant difference in 5-year disease-free survival between MIAB (100%) and EUS-FNAB (97.1%) (P = 0.27). CONCLUSION: MIAB is safe, with little impact on postoperative prognosis, although the procedure releases some tumor cells after damaging the SEL's pseudocapsule.

Development of a new endoscopy system to visualize bilirubin for the diagnosis of duodenogastroesophageal reflux.

OBJECTIVES: Reflux hypersensitivity (RH) is a form of refractory gastroesophageal reflux disease in which duodenogastroesophageal reflux (DGER) plays a role. This study aimed to determine the usefulness of an endoscopy system equipped with image-enhanced technology for evaluating DGER and RH. METHODS: The image enhancement mode for detecting bilirubin and calculated values were defined as the Bil mode and Bil value, respectively. First, the visibility of the Bil mode was validated for a bilirubin solution and bile concentrations ranging from 0.01% to 100% (0.002-20 mg/dL). Second, visibility scores of the Bil mode, when applied to the porcine esophagus sprayed with a bilirubin solution, were compared to those of the blue laser imaging (BLI) and white light imaging (WLI) modes. Third, a clinical study was conducted to determine the correlations between esophageal Bil values and the number of nonacid reflux events (NNRE) during multichannel intraluminal impedance-pH monitoring as well as the utility of esophageal Bil values for the differential diagnosis of RH. RESULTS: Bilirubin solution and bile concentrations higher than 1% were visualized in red using the Bil mode. The visibility score was significantly higher with the Bil mode than with the BLI and WLI modes for 1% to 6% bilirubin solutions (P < 0.05). The esophageal Bil value and NNRE were significantly positively correlated (P = 0.031). The area under the receiver operating characteristic curve for the differential diagnosis of RH was 0.817. CONCLUSION: The Bil mode can detect bilirubin with high accuracy and could be used to evaluate DGER in clinical practice.

Validation of a claims-based algorithm to identify cases of ulcerative colitis in Japan.

BACKGROUND AND AIM: The prevalence of ulcerative colitis (UC) is increasing in Japan. Validated claims-based definitions are required to investigate the epidemiology of UC and its treatment and disease course in clinical practice. This study aimed to develop a claims-based algorithm for UC in Japan. METHODS: A committee of epidemiologists, gastroenterologists, and internal medicine physicians developed a claims-based definition for UC, based on diagnostic codes and claims for UC treatments, procedures (cytapheresis), or surgery (postoperative claims). Claims data and medical records for a random sample of 200 cases per site at two large tertiary care academic centers in Japan were used to calculate the positive predictive value (PPV) of the algorithm for three gold standards of diagnosis, defined as physician diagnosis in the medical records, adjudicated cases, or registration in the Japanese Intractable Disease Registry (IDR). RESULTS: Overall, 1139 claims-defined UC cases were identified. Among 393 randomly sampled cases (mean age 44; 48% female), 94% had received ≥ 1 systemic treatment (immunosuppressants, tumor necrosis factor inhibitors, corticosteroids, or antidiarrheals), 7% had cytapheresis, and 7% had postoperative claims. When physician diagnosis was used as a gold standard, PPV was 90.6% (95% confidence interval [CI]: 87.7-93.5). PPV with expert adjudication was also 90.6% (95% CI: 87.7-93.5). PPVs with enrollment in the IDR as gold standard were lower at 41.5% (95% CI: 36.6-46.3) due to incomplete case registration. CONCLUSIONS: The claims-based algorithm developed for use in Japan is likely to identify UC cases with high PPV for clinical studies using administrative claims databases.

The treatment effects of acotiamide in esophagogastric outflow obstruction: a prospective longitudinal observational study.

OBJECTIVES: We have found that an altered lower esophageal sphincter (LES) accommodation response is an underlying cause of esophagogastric junction outflow obstruction (EGJOO). The objective of this study was to examine the treatment effect of acotiamide, a prokinetic agent which improves impaired gastric accommodation in functional dyspepsia, in patients with EGJOO. METHODS: A prospective observational longitudinal study was conducted between October 2014 and March 2020. Acotiamide (100 mg, 3 times a day) was administered to 25 patients with EGJOO for 4 weeks. High-resolution manometry (HRM) was performed just before and after 4 weeks of treatment. RESULTS: As the primary outcome, the extent of integrated relaxation pressure (IRP) after treatment (14.6, 12.1-22.0 mmHg) was significantly lower than that before treatment (19.4, 17.1-27.4 mmHg). The extent of LES accommodation index after treatment (32.7, 21.0-40.0 mmHg) was also significantly lower than that before treatment (39.3, 31.2-50.2 mmHg). Acotiamide normalized the IRP (< 15 mmHg) in 13 of 25 patients with EGJOO (52%), and the IRP was decreased in 20 of 25 patients with EGJOO (80%). As the secondary outcome, the total FSSG score in 25 patients with EGJOO before and after acotiamide treatment showed no significant difference. In a sub-analysis of 13 patients in whom EGJOO was normalized by acotiamide, however, dysphagia was reported to be significantly improved by acotiamide. CONCLUSIONS: Acotiamide has a treatment effect on patients with EGJOO via a reduction in the IRP level through the lowering of both the basal LES pressure and LES accommodation response. Dysphagia is a key symptom to be evaluated and treated in patients with EGJOO.

Discriminant equation using mucosally expressed cytokines and transcription factor for making definite diagnosis of inflammatory bowel disease unclassified.

BACKGROUND: The pathological conditions of UC and CD involved in inflammatory bowel disease-unclassified (IBD-U), UC with primary sclerosing cholangitis (PSC-UC), and UC with autoimmune pancreatitis type 2 (AIP-UC) remain unclear. Therefore, it is difficult to decide the appropriate treatments for these subtypes of UC. Our aim was to examine whether the discriminant equation using the mucosally expressed mediators designed as our previous study for IBD, could characterize IBD-U, PSC-UC, or AIP-UC. METHODS: A total of 56 patients including UC (n = 24), CD (n = 15), IBD-U (n = 10), PSC-UC (n = 4), and AIP-UC (n = 3), along with 9 control patients were enrolled in this study. Mucosally expressed inflammatory mediators related to Th1, Th2, Th17, and Treg were measured using quantitative PCR in endoscopic biopsies from the inflamed intestines of the patients. The IBD-U, PSC-UC or AIP-UC were characterized using discriminant analysis and principle component analysis. RESULTS: Through discriminant analyses, combinations of 3 to 7 inflammatory mediators were used to discriminate between UC and CD. Moreover, the identified 3 markers could diagnose patients with IBD-U as UC or CD with high accuracy. The distribution graph of inflammatory mediators using the principal component analysis revealed that PSC-UC and AIP-UC exhibited CD-like and UC-like features, respectively. CONCLUSIONS: The discriminant equation using mucosally expressed mediators of IL-13, IL-21 and T-bet can be used as a universal diagnostic tool not only for IBD-U but also to assess pathological conditions in PSC-UC and AIP-UC.

Clinical Characterization of Vonoprazan-Refractory Gastroesophageal Reflux Disease.

INTRODUCTION: The newly developed vonoprazan (a potassium-competitive acid blocker) has a greater ability to suppress gastric acid production than convention proton pump inhibitors (PPIs). The objective of the present study was to determine how vonoprazan influences the pathogenesis of refractory gastroesophageal reflux disease (GERD) in clinical practice. METHODS: Between March 2013 and November 2018, a total of 73 refractory GERD patients (34 in the conventional PPI group versus 39 in the vonoprazan group) were enrolled in this retrospective study. We then compared the underlying disease conditions between the 2 groups, examined by high-resolution manometry and multichannel intraluminal impedance/pH (MII-pH) monitoring. RESULTS: There was a significant difference in the proportion of underlying disease conditions, including erosive esophagitis, non-erosive reflux disease, reflux hypersensitivity, functional heartburn and oesophageal motility disorder (EMD), between the conventional PPI (6, 14, 23, 40 and 17% respectively) and vonoprazan groups (0, 0, 10, 49, and 41% respectively; p < 0.01). No cases of acid-related GERD were observed in the vonoprazan group. When the EMD patients were excluded, the lower oesophageal acid exposure time of the vonoprazan group (0.1% [0.0-0.5%], n = 23) was significantly lower than that of the conventional PPI group (0.35% [0.1-3.9%], n = 28; p < 0.05), and the gastric pH <4 holding time of the vonoprazan group (7.7% [0.7-34.5%]) was also significantly lower than that of the conventional PPI group (61.6% [49.4-74.3%], p < 0.01). CONCLUSIONS: Vonoprazan serves as a diagnostic tool to exclude acid-related GERD.

Interleukin-1ß as a Predictor of Glucocorticoid Response in Ulcerative Colitis.

BACKGROUND/AIM: Currently, there are no established biomarkers to differentiate between glucocorticoid (GC)-resistant and GC-sensitive ulcerative colitis (UC); however, interleukin (IL)-1ß could be one such candidate biomarker. The aim of this study was to investigate whether mucosally expressed IL-1ß could predict the response to GC in patients with UC. METHODS: A total of 27 mucosal tissue samples from 10 patients with GC-resistant UC (GC-resistant group), 9 patients with GC-sensitive UC (GC-sensitive group), and 8 control patients (control group) were analyzed by qRT-PCR for the expression of IL-1ß, GC receptor α (GRα), GRß, and other inflammatory mediators. Rachmilewitz endoscopic index (REI) between the GC-resistant and GC-sensitive groups was matched to avoid any potential influence of inflammation. RESULTS: The REI did not significantly differ between the GC-resistant and GC-sensitive groups. Mucosally expressed IL-1ß levels in the GC-resistant group were significantly higher than those in the GC-sensitive group. However, there were no significant differences in the expression levels of GRα, GRß, and other inflammatory mediators between the 2 groups. We could distinguish between the GC-resistant and GC-sensitive groups with a sensitivity of 90.0% and specificity of 77.8% based on mucosally expressed IL-1ß. CONCLUSIONS: Mucosally expressed IL-1ß can be used as a predictor of GC response in patients with UC.

Superiority of mucosal incision-assisted biopsy over ultrasound-guided fine needle aspiration biopsy in diagnosing small gastric subepithelial lesions: a propensity score matching analysis.

BACKGROUND: Gastric subepithelial lesions, including gastrointestinal stromal tumors, are often found during routine gastroscopy. While endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) has been the gold standard for diagnosing gastric subepithelial lesions, alternative open biopsy procedures, such as mucosal incision-assisted biopsy (MIAB) has been reported useful. The aim of this study is to evaluate the efficacy of MIAB for the diagnosis of gastric SELs compared with EUS-FNAB. METHODS: We retrospectively analyzed medical records of 177 consecutive patients with gastric SELs who underwent either MIAB or EUS-FNAB at five hospitals in Japan between January 2010 and January 2018. Diagnostic yield, procedural time, and adverse event rates for the two procedures were evaluated before and after propensity-score matching. RESULTS: No major procedure-related adverse events were observed in either group. Both procedures yielded highly-accurate diagnoses once large enough samples were obtained; however, such successful sampling was more often accomplished by MIAB than by EUS-FNAB, especially for small SELs. As a result, MIAB provided better diagnostic yields for SELs smaller than 20-mm diameter. The diagnostic yields of both procedures were comparable for SELs larger than 20-mm diameter; however, MIAB required significantly longer procedural time (approximately 13 min) compared with EUS-FNAB. CONCLUSIONS: Although MIAB required longer procedural time, it outperformed EUS-FNAB when diagnosing gastric SELs smaller than 20-mm diameter.

The Altered Mucosal Barrier Function in the Duodenum Plays a Role in the Pathogenesis of Functional Dyspepsia.

BACKGROUND: An altered gastrointestinal barrier function is reportedly associated with the pathogenesis of functional dyspepsia (FD); however, the pathogenesis of FD has not yet been fully elucidated. AIMS: The objective of the present study was to determine whether the mucosal barrier function is impaired in patients with FD and to investigate the mechanisms underlying FD. METHODS: The present study included patients with FD (FD group, n = 24), non-FD patients with abdominal symptoms (symptomatic control group, n = 14), and patients with no abdominal symptoms (asymptomatic control group, n = 20). The groups were compared regarding the mucosal electrical impedance (MI) values of the stomach and duodenum, which were measured using a tissue conductance meter during esophagogastroduodenoscopy. RESULTS: There were no significant differences between the three groups in the MI of the stomach. In contrast, the duodenal MI of the FD group (17.8 ± 4.3 Ω) was significantly lower than those of the symptomatic control group (27.2 ± 6.4 Ω, p < 0.0001) and asymptomatic control group (23.0 ± 7.4 Ω, p = 0.016). The expression of zonula occludens-1 (ZO-1) was significantly lower in the FD group than in the symptomatic control group (p = 0.011), where ZO-1 was positively correlated with the duodenal MI (ß = 0.513, p = 0.017). The interleukin (IL)-1ß expression was significantly higher in the FD group than in the symptomatic control group (p = 0.041), where IL-1ß was inversely correlated with the duodenal MI (ß = - 0.600, p = 0.004). CONCLUSIONS: The mucosal barrier function of the duodenum was altered in patients with FD. Both a decreased ZO-1 and increased IL-1ß may play a role in the pathogenesis of FD.

Objective validity of the Japan Narrow-Band Imaging Expert Team classification system for the differential diagnosis of colorectal polyps.

BACKGROUND AND AIM: The Japan Narrow-Band Imaging (NBI) Expert Team (JNET) classification is a recently proposed NBI magnifying endoscopy-based classification system for colorectal tumors. Although the usefulness of this system has been reported by JNET experts, its objective validity remains unclear. We tested its validity and usefulness for the diagnosis of colorectal polyps by including colonoscopy experts and non-experts as test participants. METHODS: Forty NBI images of polyps of various JNET types were shown to 22 doctors (11 experts and 11 non-gastrointestinal [GI] trainees) who had not examined the patients. The doctors diagnosed the polyps based solely on the surface and vessel patterns in the magnified images and the JNET classification system. Concordance rates of their diagnoses with the pathological findings of the polyps were determined, and the results for experts and non-GI trainees were compared. RESULTS: Both for colonoscopy experts and non-GI trainees, the JNET classification system was particularly useful for classifying polyps as benign or malignant. Although the accuracy rates for classifying polyps into each JNET type varied among colonoscopy experts, those who were familiar with the JNET classification system were able to diagnose polyps with approximately 90% accuracy. Common mistakes were attributable to misunderstandings of the wording in the JNET classification chart and lack of proper training. CONCLUSION: The JNET classification system is a practical approach for the diagnosis of colorectal polyps. Training is required even for experienced colonoscopists to adopt the system properly. Common pitfalls must be shared among colonoscopists to improve the accuracy of the diagnosis.

Mucosal incision-assisted biopsy versus endoscopic ultrasound-guided fine-needle aspiration with a rapid on-site evaluation for gastric subepithelial lesions: A randomized cross-over study.

OBJECTIVES: This study aimed to compare the diagnostic yield of mucosal incision-assisted biopsy (MIAB) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with a rapid on-site evaluation (ROSE) for gastric subepithelial lesions (SEL) suspected of being gastrointestinal stromal tumors (GIST) with an intraluminal growth pattern. METHODS: This was a prospective randomized, cross-over multicenter study. The primary outcome was the diagnostic yield of EUS-FNA and MIAB. The secondary outcomes were the technical success rate, complication rate, procedure time and biopsy frequency. RESULTS: A total of 47 patients were randomized to the MIAB group (n = 23) and EUS-FNA group (n = 24). There was no significant difference in the diagnostic yield of MIAB and EUS-FNA (91.3% vs 70.8%, P = 0.0746). The complication rates of MIAB and EUS-FNA did not differ to a statistically significant extent. The mean procedure time in the MIAB group was significantly longer than that in the EUS-FNA group (34 vs 26 min, P = 0.0011). CONCLUSIONS: The diagnostic yield of MIAB was satisfactorily as high as EUS-FNA with ROSE for gastric SEL with an intraluminal growth pattern.

Splash M-knife versus Flush Knife BT in the technical outcomes of endoscopic submucosal dissection for early gastric cancer: a propensity score matching analysis.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a standard treatment for early gastric cancer. A new multi-functional ESD device was developed to achieve complete ESD with a single device. A metal plate attached to its distal sheath achieves better hemostasis during the procedure than the other needle-knife device, Flush Knife BT®, that has been conventionally used. The aim of this study was to compare the technical outcomes of ESD for early gastric cancer using the Splash M-Knife® with those using the Flush Knife BT. METHODS: We conducted a retrospective review of the case records of 149 patients with early gastric cancer treated with ESD using the needle-type ESD knives between January 2012 and August 2016 at Kitakyushu Municipal Medical Center. Lesions treated with ESD using the Splash M-knife (ESD-M) and the Flush Knife BT (ESD-F) were compared. Multivariate analyses and propensity score matching were used to compensate for the differences in age, gender, underlying disease, antithrombotic drug use, lesion location, lesion position, macroscopic type, tumor size, presence of ulceration, operator level and types of electrosurgical unit used. The primary endpoint was the requirement to use hemostatic forceps in the two groups. The secondary endpoints of procedure time, en bloc and complete resection rates, and adverse events rates were evaluated for the two groups. RESULTS: There were 73 patients in the ESD-M group, and 76 patients in the ESD-F group. Propensity score matching analysis created 45 matched pairs. Adjusted comparisons between the two groups showed a significantly lower usage rate of hemostatic forceps in the ESD-M group than in the ESD-F group (6.7% vs 84.4%, p < 0.001). Treatment outcomes showed an en bloc resection rate of 100% in both groups; complete resection rate of 95.6% vs 100%, p = 0.49; median procedure time of 74.0 min vs 71.0 min, p = 0.90; post-procedure bleeding of 2.2% vs 2.2%, p = 1, in the ESD-M and ESD-F groups, respectively. There were no perforations in either group. CONCLUSIONS: ESD-M appeared to reduce the usage of hemostatic forceps during ESD for early gastric cancer without increasing the adverse effects. Thus, it may contribute to a reduction in the total ESD cost.