Randomized controlled trial of remimazolam compared with placebo in Japanese patients undergoing upper gastrointestinal endoscopy: Phase III investigator-initiated clinical trial

OBJECTIVES

To assess the effectiveness of remimazolam against normal saline (placebo) as a sedative agent for endoscopy in a multicenter, randomized, double-blind, investigator-initiated phase III controlled trial.

METHODS

We included 48 Japanese patients undergoing upper gastrointestinal endoscopy. For the procedure, an initial remimazolam dose of 3 mg and additional doses of 1 mg were administered, as determined in the phase II clinical study. The primary study end-point was the successful sedation rate during gastrointestinal endoscopy, determined as a Modified Observer's Assessment of Alertness/Sedation score ≤4 before the start of endoscopy, the completion of gastrointestinal endoscopy, and two or fewer additional doses per 6 min.

RESULTS

The successful endoscopy sedation rates were 91.9% and 9.1% in the remimazolam and placebo groups, respectively (P < 0.01). The time from the end of endoscopy to arousal was 0.0 (0.0-0.0) min for both groups. The number of additional doses required to achieve sedation was lower in the remimazolam group than that in the placebo group (P < 0.01).

CONCLUSIONS

Remimazolam demonstrated a significantly higher sedation effect during upper gastrointestinal endoscopy in Japanese patients with safe and fast recovery compared with placebo.

A single-center prospective study on pain alleviation during peroral upper endoscopy with an ultrathin endoscope

BACKGROUND

The efficacy of transnasal endoscopy using an ultrathin endoscope has been reported in several studies. However, few studies regarding peroral endoscopy with ultrathin endoscopes with high resolution have been reported. This study investigates the pain alleviation of peroral endoscopy with an ultrathin endoscope.

METHODS

Patients with a history of peroral endoscopy using a conventional, normal-diameter scope with no sedation who underwent peroral esophagogastroduodenoscopy (EGD) using a thin scope between April-July 2022 were included in this study. After the procedure, the patients completed a questionnaire evaluating pain during the examination and willingness to repeat the procedure. The physicians were surveyed regarding their level of satisfaction. The primary endpoint was patient satisfaction, which corresponded to the rate of patients who rated the thin endoscope as more comfortable or somewhat more comfortable than the previously-used, conventional endoscope.

RESULTS

One hundred and forty-five patients were included in the analyses. Patient satisfaction was achieved in 86.2% (125/145) of patients. The median visual analog scale pain score was 3 (0-7) points in this study, which is significantly lower than the pain score after the previous endoscopy (5 (0-10) points; p < 0.001). In addition, 96% (24/25) of patients who underwent EGD by an expert and 95.8% (115/120) who underwent EGD by a non-expert were willing to repeat endoscopy using the thin scope (p = 0.69).

CONCLUSION

Peroral endoscopy using a thin scope reduces patient pain regardless of the endoscopist's experience.

Management of colorectal high-grade dysplasia or cancer resected by cold snare polypectomy: a multicenter exploratory study

BACKGROUND

The clinical course and surveillance strategy for patients who undergo cold snare polypectomy (CSP) for high-grade dysplasia (HGD) or cancer is unclear. We investigated the management of colorectal HGDs and cancers following CSP.

METHODS

This Japanese nationwide multicenter exploratory study was retrospectively conducted on patients who had undergone CSP for colorectal HGDs or cancers and follow-up colonoscopy at least once from 2014 to 2020. We investigated the detection rate of CSP scars, local recurrence rate (LRR), risk factors for local recurrence, and follow-up strategy. This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000043670).

RESULTS

We included 155 patients with 156 lesions. CSP scars were identified in 22 (31.4%), 41 (54.7%), and 10 (90.9%) patients with curative, borderline, and non-curative resection, respectively. Among them, residual tumors were observed in one (4.5%), six (14.6%), and three (30.0%) cases, respectively. The total LRR was 13.7% (95% confidence interval: 6.8-23.8). R1 resection cases (either horizontal or vertical margins positive for tumors) were associated with local recurrence (p = 0.031). Salvage endoscopic and surgical resections were performed on 21 and 10 patients, respectively. Among them, the proportion of endoscopically suspected residual tumors was significantly higher (p < 0.001) in the residual tumor-positive group (100%) than in the residual tumor-negative group (28.6%).

CONCLUSIONS

LRR after CSP for HGDs or cancers was 13.7% based on scar-identified cases. Salvage endoscopic or surgical resection should be performed according to the curability of the lesion and endoscopic findings during colonoscopic surveillance.

Randomized controlled trial comparing conventional and traction endoscopic submucosal dissection for early colon tumor (CONNECT-C trial)

OBJECTIVES

Endoscopic submucosal dissection (ESD) is a widely used treatment for early gastrointestinal cancer. However, colon ESD remains challenging. Previous studies on colon ESD using the traction method used a small sample, single-center design, providing insufficient evidence of this procedure's efficacy. We thus aimed to investigate the efficacy and safety of the traction method in colon ESD in this multicenter randomized trial.

METHODS

We conducted a prospective, multicenter, randomized, two-arm controlled trial at 10 facilities in Japan. A 1:1 allocation was conducted for the conventional ESD (C-ESD) and traction ESD (T-ESD) groups. The primary end-point was ESD procedure time.

RESULTS

We included 128 C-ESD and 123 T-ESD cases from April 2020 to August 2021. The median procedure times for C-ESD and T-ESD were 61 (40-100) and 53 (40-76) min (P = 0.18), respectively, and no significant differences were observed between the groups. Subgroup analysis showed that the median procedure times for patients with a lesion diameter of ≥30 mm in the C-ESD and T-ESD groups were 89 (57-80) and 69 (50-104) min (P = 0.05), respectively, and for nonexpert operators were 81 (62-120) and 64 (52-109) min (P = 0.07), respectively.

CONCLUSIONS

The traction method did not contribute to a significantly shortened ESD procedure time. However, this method may be useful when the tumor diameter is large or if the procedure is conducted by nonexpert endoscopists.

First dose-ranging study of remimazolam in Japanese patients undergoing gastrointestinal endoscopy: Phase II investigator-initiated clinical trial

OBJECTIVES

Remimazolam, an ultra-short-acting benzodiazepine, has been used for procedural sedation in the United States. We conducted an investigator-initiated clinical trial to determine the appropriate dose of remimazolam required for sedation during gastrointestinal endoscopy in Japanese subjects.

METHODS

In this single-center, open-label, uncontrolled, phase II trial, a three-stage cohort investigated the appropriate initial and additional doses of remimazolam required for gastrointestinal endoscopy. This study was designed with advice from the Pharmaceuticals and Medical Devices Agency. The initial and additional doses were 2 mg and 1 mg/dose, 3 mg and 1 mg/dose, and 5 mg and 2 mg/dose in cohorts 1, 2, and 3, respectively. Each cohort included 10 cases of upper gastrointestinal endoscopy and colonoscopy. The primary end-point was the success rate of sedation during gastrointestinal endoscopy.

RESULTS

Sedation was successful in all gastrointestinal endoscopies in cohorts 1 and 2. In cohort 1, sedation was achieved in five (25.0%) and 10 (50.0%) participants with the initial dose and total dose (initial dose + additional dose ≤ the initial dose of the next cohort), respectively, before endoscopy. In cohort 2, sedation was achieved in 11 (55.0%) and 18 (90.0%) participants with the initial dose and total dose, respectively, before endoscopy. No patient in either cohort lost consciousness or required flumazenil or manual ventilation.

CONCLUSION

Initial and additional doses of 3 mg and 1 mg/dose of remimazolam, respectively, were shown to be effective and safe for sedation during gastrointestinal endoscopy in Japanese patients.

Self-completion method of endoscopic submucosal dissection using the Endosaber for treating colorectal neoplasms (with video)

Endoscopic submucosal dissection (ESD) is effective for the treatment of colorectal neoplasms. We have developed a self-completion ESD (S-ESD) using Endosaber without requiring additional instruments or assistance. This prospective cohort study was conducted to investigate the feasibility of S-ESD for colorectal neoplasms. Patients with colorectal neoplasms measuring 20–40 mm in size were enrolled. A single operator, without assistance, performed ESD using only the Endosaber. The primary outcome was the success rate of S-ESD. Secondary outcomes included procedure time, the rates of en bloc, complete, and curative resection, and complication rates, including the incidence of perforation and delayed bleeding. In total, 15 patients with 15 lesions were enrolled. The median size of the resected lesions was 28 mm (interquartile range 25–29 mm). S-ESD success rate of 100% was achieved. The median procedure time was 44 min (29.5–53.5 min). We observed en bloc, complete, and curative resection rates of 100%, 93.3%, and 86.7%, respectively, and a complication rate of 6.7% (perforation: 0%, delayed bleeding: 6.7%). S-ESD for colorectal neoplasms was successfully performed with favorable treatment outcomes and low complication rates. S-ESD reduces the number of devices and extent of assistance, making S-ESD a simple and cost-effective procedure.

Efficacy and timing of gastrografin administration after ileus tube insertion in patients with adhesive small bowel obstruction

BACKGROUND AND STUDY AIMS

Gastrografin administration (GA) is performed for adhesive small bowel obstruction (ASBO) in cases when decompression therapy using an ileus tube fails to relieve the obstruction. This study evaluated the efficacy of GA and optimized its timing after ileus tube insertion.

PATIENTS AND METHODS

In this retrospective study, we evaluated data from patients with ASBO admitted between January 2014 and August 2018 and included patients who underwent ileus tube intubation and GA. The patients were classified as those treated with GA within 48 h after admission (early GA [EGA]) and those treated later with GA (delayed GA [DGA]). Propensity score matching was performed to compensate for differences between the groups. Short-term outcomes were compared between the two groups.

RESULTS

We included 67 and 80 patients in the EGA and DGA groups, respectively, and 55 pairs with similar background characteristics were matched. The rates of successful conservative management were 87.3% (48/55) in the EGA group, 96.4% (53/55) in the DGA group, and 91.8% (101/110) in the entire sample. The median period of ileus tube insertion in the DGA group was significantly lower than that in the EGA group, whereas other outcomes did not significantly differ between the groups. Aspiration pneumonia occurred in one patient in the EGA group.

CONCLUSIONS

GA with an ileus tube achieved a high rate of successful conservative management. Follow-up using decompression with an ileus tube for at least 48 h after admission is recommended in patients with ASBO.

The Ideal Helicobacter pylori Treatment for the Present and the Future

BACKGROUND

Helicobacter pylori eradication treatments are widely performed to improve gastric mucosal inflammation, promote ulcer healing, and reduce the incidence of gastric cancer. However, there are several issues associated with H. pylori eradication treatment. First, various treatment regimens are currently used worldwide, and the standard treatment varies with region and country. Second, the antimicrobial resistance of H. pylori is increasing due to indiscriminate antibiotic use. Finally, gut microbiota dysbiosis is potentially induced by H. pylori treatment.

SUMMARY

Based on current international guidelines and a network meta-analysis comparing the effects of various treatment regimens, nonbismuth quadruple therapies for 10-14 days and vonoprazan-based triple therapy for 7 days are the currently recommended H. pylori treatment regimens. These regimens show good eradication rates of approximately 90%, even in areas where antimicrobial-resistant strains are highly prevalent. However, these regimens still have inherent drawbacks that may promote further increases in antimicrobial resistance and induce gut microbiota dysbiosis because of the empiric use of multiple antibiotics. Key Message: The ideal concept for the present and future H. pylori eradication treatment involves "a simple, cost-effective strategy that fosters compliance without having a negative impact on the gut microbiota or contributing to future antimicrobial resistance." One interesting possibility that may fulfill this concept is a dual therapy involving vonoprazan and amoxicillin. This is the simplest treatment regimen that provides acceptable eradication rates, improves safety and tolerability, and minimizes the potential for increasing antimicrobial resistance or causing gut microbiota dysbiosis.

Long term impact of vonoprazan-based Helicobacter pylori treatment on gut microbiota and its relation to post-treatment body weight changes

BACKGROUND

Vonoprazan-based Helicobacter pylori (H. pylori) treatment is highly effective in eradicating the target bacteria; however, its post-1-year impact on gut microbiota is unknown. This study evaluated the impact of vonoprazan-based H. pylori therapy on gut microbiota 1-year post-therapy and investigated the relationship between body weight changes and post-therapy gut microbiota perturbations.

MATERIALS AND METHODS

Between March and May 2019, 43 patients with H. pylori infections received either vonoprazan/amoxicillin (VA) or vonoprazan/amoxicillin/clarithromycin (VAC) therapy. Fecal samples were collected prior to treatment and 1 year after treatment. The alpha and beta diversities and the bacterial taxa composition ratios were determined using polymerase chain reaction amplification of the V3-V4 region of the 16S ribosomal RNA gene. The correlation between body weight changes and relative abundances of genera post-therapy was also analyzed.

RESULTS

Among the 43 patients, 18 received VA therapy and 21 received VAC therapy. One year after treatment, the alpha diversity was significantly higher in both the treatment groups (p < .001, using observed operational taxonomic units and Chao1 index), and beta diversity was significantly different in both the groups (p = .001, using unweighted UniFrac distance) compared with baseline findings. Significant positive correlations were found between body weight changes and the relative abundances of Coprococcus spp. (p = .037) and Odoribacter spp. (p = .022) post-therapy.

CONCLUSION

Vonoprazan-based H. pylori therapies are associated with long-term impacts on gut microbiota, including effects on bacterial species richness, and potentially affect metabolism by altering the microbiota.

TRIAL REGISTRATION NUMBER

UMIN000040025.

Lower impact of vonoprazan-amoxicillin dual therapy on gut microbiota for Helicobacter pylori eradication

BACKGROUND AND AIM

Helicobacter pylori eradication can disrupt the gut microbiome. Here, we investigated the short-term impact of minimum antibiotic treatment-a 7-day vonoprazan and low-dose amoxicillin regimen (VA-dual therapy)-on gut microbiota and compared it with that of vonoprazan-based triple therapy (VAC-triple therapy).

METHODS

Fifty-nine patients with H. pylori infection were recruited (UMIN000034140) from March to May 2019 and randomly assigned to the VAC-triple therapy or VA-dual therapy groups, according to the first-line H. pylori treatment received. Fecal samples were collected before treatment initiation and 1 and 8 weeks after eradication therapy completion. The composition ratios of the bacterial taxa and the alpha and beta diversities were evaluated in both groups via polymerase chain reaction amplification of the V3-V4 region of the 16S rRNA gene and sequencing using the MiSeq system.

RESULTS

Nineteen patients were assigned to the VA-dual group and 24 to the VAC-triple group. Compared with baseline, the alpha diversity reduced significantly 1 and 8 weeks after VAC-triple therapy. However, for VA-dual therapy, the alpha diversities at 1 and 8 weeks after the treatment did not change significantly compared with those at baseline. Additionally, the beta diversity differed significantly between baseline and 1 and 8 weeks after VAC-triple therapy. VAC-triple therapy led to significant alteration in the relative abundance of Actinobacteria at the phylum level and Collinsella, Blautia, and Streptococcus at the genus level.

CONCLUSIONS

Compared with VAC-triple therapy, VA-dual therapy induced minimal changes in the diversity and relative abundance of gut microbiota.

Diagnostic Ability of High-definition Imaging Using Ultraslim Endoscopes in Early Gastric Cancer

Purpose

It is unclear whether high-definition (HD) imaging improves visibility and diagnostic ability in early gastric cancer (EGC) compared with standard-definition (SD) imaging. We aimed to compare the diagnostic performance and visibility scores of HD and SD ultraslim endoscopes in EGC.

Materials and Methods

We used HD and SD ultraslim endoscopes to obtain 60 images with similar compositions of gastric environments. Of the 60 images, 30 showed EGC (15 images for each modality) and 30 showed no EGC (15 images for each modality). Seventeen endoscopists evaluated the presence and location of the lesions in each image. Diagnostic ability was compared between modalities. The color difference between a lesion and the surrounding mucosa (ΔE) was measured and compared between the modalities.

Results

The ability of HD to detect EGC was significantly higher than that of SD (accuracy: 80.8% vs. 71.6%, P=0.017; sensitivity: 94.9% vs. 76.5%, P<0.001; positive predictive value, 76.2% vs. 55.3%, P<0.001; and negative predictive value (NPV), 94.1% vs. 73.5%, P<0.001). The ability of HD to determine the horizontal extent of EGC was significantly higher than that of SD (accuracy: 71.0% vs. 57.8%, P=0.004; sensitivity: 75.3% vs. 49.0%, P<0.001; NPV, 72.9% vs. 55.9%, P<0.001; and area under the curve: 0.891 vs. 0.631, P=0.038). The mean ΔE was significantly higher for HD than for SD (10.3 vs. 5.9, P=0.011).

Conclusions

The HD ultraslim endoscope showed a higher diagnostic performance in EGC than the SD endoscope because it provided good color contrast.

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.

Efficacy of Full-Spectrum Endoscopy to Visualize the Major Duodenal Papilla in Patients with Familial Adenomatous Polyposis

BACKGROUND AND AIMS

Duodenal cancer is one of the extracolonic malignancies with known mortality in familial adenomatous polyposis (FAP) patients. Visualization of the major duodenal papilla (MDP) with a standard esophagogastroduodenoscopy (EGD) is currently insufficient because of the limited field of view. Full-spectrum endoscopy (FUSE), utilizing double imagers located on the front and side of the endoscopic tip, provides a wider field of view up to 245 degrees. The aim of this study was to evaluate the efficacy of FUSE in visualizing MDP in patients with FAP.

METHODS

This study was a single-center retrospective study including 49 FAP patients undergoing surveillance at our institution. EGD was performed by qualified endoscopists using FUSE, and visibility of the MDP was evaluated. All examinations were video-recorded, and the clips for individual patient were edited to forward view images alone (conventional group) and 2-view images of the duodenum (forward and side-view [FUSE group]). Three other qualified external endoscopists independently reviewed the videos and compared the visibility of MDP between the conventional and the FUSE groups. Primary endpoint was the rate of Type 1 visibility (whole area of the papilla) in off-site video reviews. We also assessed MDP visibility on-site as secondary endpoint.

RESULTS

The rate of type 1 MDP visibility was significantly higher in the FUSE group than conventional group in both on-site (32.6/100%, p < 0.001) and off-site reviews (8.2, 16.3, 14.3/100, 98, and 100%, p < 0.001).

CONCLUSIONS

FUSE is recommended in screening and surveillance EGD to better visualize MDP in FAP patients.

Minimizing endoscopist facial exposure to droplets: Optimal patient-endoscopist distance and use of a barrier device

BACKGROUND AND AIM

Minimizing endoscopist exposure to bodily fluids is important for reducing the risk of infection transmission. This study investigated the patient-endoscopist vertical distance necessary to minimize an endoscopist's facial exposure to a patient's visible droplets during upper gastrointestinal endoscopy and the ability of a new device to prevent droplets from reaching the endoscopist's face.

METHODS

A model was developed to simulate a patient experiencing a forceful cough during an upper gastrointestinal endoscopy with a model endoscopist. Fluorescent dye was expelled from the model patient's mouth towards the model endoscopist during simulated coughs; dye adhesion to the model endoscopist's face was evaluated using ultraviolet light. The simulation was repeated with the model patient positioned 70-100 cm above the floor, with and without a barrier to shield the patient's face. The accuracy of the cough simulation model and the relationship between patient-endoscopist vertical distance and endoscopist's facial exposure were evaluated.

RESULTS

The flow dynamics of the cough simulation model were similar to that of an actual human cough. There was a significant inverse correlation between the patient-endoscopist vertical distance and the model endoscopist's facial exposure, with positive exposures decreasing from 87% at 70 cm to 0% at 100 cm (P < 0.001). The barrier device prevented facial exposure to droplets at all distances.

CONCLUSIONS

We found that positioning the patient at least 100 cm below the top of the endoscopist's head or using a barrier device minimized the endoscopist's facial exposure to visible droplets during upper gastrointestinal endoscopy.

Impact of body size on first-line Helicobacter pylori eradication success using vonoprazan and amoxicillin dual therapy

BACKGROUND

As a first-line therapy for Helicobacter pylori, dual therapy with vonoprazan and amoxicillin (VA-dual) provides an eradication rate similar to that of vonoprazan-based triple therapy. As the factors associated with the eradication rate of H. pylori with VA-dual are unknown,we investigated them in this study.

MATERIALS AND METHODS

Overall, 163 patients diagnosed with H. pylori infection received VA-dual (vonoprazan 20 mg twice daily and amoxicillin 750 mg twice daily for 7 d). The association between successful H. pylori eradication and the following patient clinical factors was analyzed: sex, age, height, weight, body surface area (BSA), body mass index (BMI), history of early gastric carcinoma and peptic ulcer, comorbidity of cirrhosis, alcohol consumption habit, smoking habit, common use of proton pump inhibitors, and concomitant use of drugs that are substratesof cytochrome P450 (CYP) 3A4. The association between post-eradication adverse events and clinical factors was analyzed retrospectively.

RESULTS

Successful H. pylori eradication was associated with a lower BSA (eradication rate: 90.8% in patients with BSA <1.723 vs. 79.6% in those with BSA ≥1.723; p = 0.045). The incidence of adverse events was higher in women than in men (adverse events: 40.0% in women vs. 19.4% in men; p = 0.004).

CONCLUSIONS

Successful H. pylori eradication with VA-dual was associated with the small body size of patients. This therapy may have to be adjusted per body size.

Efficacy and safety of grasping forceps-assisted endoscopic resection for gastric neoplasms: A multi-centre retrospective study

BACKGROUND

Endoscopic submucosal dissection (ESD) is widely accepted for early gastric cancer (EGC) without lymph node metastasis, although ESD is challenging, even for small lesions, in the greater curvature (GC) of the upper (U) and middle (M) thirds of the stomach. Grasping forceps-assisted endoscopic resection (GF-ER) is a type of endoscopic mucosal resection that is performed via a double-channel endoscope.

AIM

To investigate the safety and efficacy of GF-ER vs ESD in the GC of the stomach’s U and M regions.

METHODS

We retrospectively reviewed the medical records of 506 patients who underwent ER of 522 EGC lesions in the stomach’s U and M regions in three institutions between January 2016 and May 2020. Nine lesions from eight patients who underwent GF-ER for EGC (the GF-ER group) were compared to 63 lesions from 63 patients who underwent ESD (the ESD group). We also performed a subgroup analysis of small lesions (≤ 10 mm) in 6 patients (7 lesions) from the GF-ER group and 20 patients (20 lesions) from the ESD group.

RESULTS

There were no statistically significant differences between the GF-ER and ESD groups in the en bloc resection rates (100% vs 100%) and the R0 resection rates (100% vs 98.4%). The median procedure time in the GF-ER group was shorter than that in the ESD group (4.0 min vs 55.0 min, P < 0.01). There were no adverse events in the GF-ER group, although five perforations (8.0%) and 1 case of postoperative bleeding (1.6%) were observed in the ESD group. When we only considered lesions that were ≤ 10 mm, the median procedure time in the GF-ER group was still shorter than that in the ESD group (4.0 min vs 35.0 min, P < 0.01). There were no adverse events in the GF-ER group, although 1 case of perforation (1.6%) were observed in the ESD group.

CONCLUSION

These findings suggest that GF-ER may be an effective therapeutic option for small lesions in the GC of the stomach’s U and M regions.

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.

High Body Mass Index Is Correlated with the Success of Vonoprazan-Based Second-Line Therapy for Helicobacter Pylori Infection

Eradication of Helicobacter pylori (Hp) is necessary for preventing peptic ulcers and stomach cancer. The potassium-competitive acid blocker vonoprazan is a gastric acid secretion inhibitor that improves the success rate of Hp eradication through its immediate and persistent inhibition of acid excretion. In Japan, first-line treatment involves a regimen in which vonoprazan is combined with amoxicillin and clarithromycin, while second-line treatment involves vonoprazan combined with amoxicillin and metronidazole. However, in contrast to the vonoprazan-based first-line therapy, no studies have investigated the factors influencing the success of vonoprazan-based second-line therapy. In this study, we therefore aimed to investigate factors related to the success of vonoprazan-based second-line therapy. We analyzed the association between the success of Hp eradication and patient factors including metronidazole/amoxicillin minimal inhibitory concentrations (MICs). MICs were measured using the Hp isolated from each patient. A receiver operating characteristic (ROC) analysis was conducted to examine continuous variables and eradication success. We reviewed the records of 33 patients (age: 34-79 years, male/female: 22/11, and body mass index (BMI): 16.1-28.8 kg/m²) who underwent vonoprazan-based second-line therapy after failure of first-line therapy at seven Japanese facilities between October 2018 and June 2019. The eradication success rate was 81.8% (27/33). ROC analysis revealed an area under the curve and BMI cutoff value of 0.796 and 23.8 kg/m², respectively. The eradication success rate was higher in patients with high BMI than in those with low BMI (p = 0.007). Our findings indicate that higher BMI is correlated with the success of vonoprazan-based second-line therapy.

Ex vivo porcine model study on the treatment outcomes of scissor-type knife versus needle-type knife in endoscopic submucosal dissection performed by trainees

Background

Endoscopic submucosal dissection (ESD) for gastrointestinal neoplasms can be technically difficult for trainee endoscopists. Presently, there is no consensus for trainees to select the endo-knife type in ESD. Therefore, we conducted a comparison study of treatment outcomes between scissors-type and needle-type knives in ESD performed by trainees in an ex vivo porcine model.

Methods

This study was conducted on trainee endoscopists who participated in ESD hands-on seminars held in August 2018 and September 2019. A total of 22 trainees from 13 institutions were divided into two groups according to their endoscopic experience. Under expert supervision, each trainee performed two ESDs in porcine models, namely, scissor-type knife (ESD-S) and needle-type knife (ESD-N). The efficacy and safety, including the procedure time and rates of self-completion, en bloc resection, and complications, were compared between ESD-S and ESD-N. In subgroup analysis, we also investigated the predictors associated with the difficulty of ESD for trainees using multivariate logistic regression analysis.

Results

Eight trainees had an experience of over 1000 endoscopies (senior trainee: S-Trainee), whereas the others had an experience of less than 1000 endoscopies (junior trainee: J-Trainee). Among the S-Trainees, no significant differences were observed in any treatment outcome between ESD-S and ESD-N. Among the J-Trainees, the total procedure and mucosal incision times were significantly shorter in ESD-S than in ESD-N [total procedure time: 16.5 min (range 10.0–31.0) vs. 22.3 min (range 10.0–38.0), P = 0.018; circumferential incision time: 10.0 min (range 6–16) vs. 17.0 min (range 5.0–31.5); P = 0.019]. Regarding complications, muscular injury occurred in two patients during ESD-N performed by J-Trainees; however, no muscular injury occurred during ESD-S. In subgroup analysis, ESD-N was an independent predictive factor of difficult ESD (odds ratio 5.28, 95% confidence interval 1.25–22.30; P = 0.024).

Conclusions

This study revealed that trainees, particularly those who have experienced less than 1000 endoscopies, should opt for the scissor-type knife to perform ESD.

Clinical impact of vonoprazan-based dual therapy with amoxicillin for H. pylori infection in a treatment-naïve cohort of junior high school students in Japan

BACKGROUND

Although 7-day triple therapy, consisting of vonoprazan, amoxicillin (AMO), and clarithromycin (CLA), is recommended for Helicobacter pylori (H. pylori) eradication in adults. However, the importance of reducing antibiotic use in pediatric patients is well recognized. Therefore, our aim was to compare the effectiveness and safety of vonoprazan and AMO (VA) dual therapy to vonoprazan-based (VAC) triple therapy for H. pylori eradication in a cohort of treatment-naïve junior high school students in Japan.

METHODS

This was a prospective observational study of second-year junior high-school students in Yurihonjo and Nikaho Cities, Japan. Between 2015 and 2017, 161 students were treated with VAC-triple therapy (20 mg vonoprazan, 750 mg AMO, and 200 mg CLA, twice a day for 7 days), while 60 students were treated with VA-dual therapy (20 mg vonoprazan and 750 mg AMO, twice a day for 7 days) since 2018. The success rate of H. pylori eradication and drug-related adverse events were compared between the two therapy groups. Intention-to-treat (ITT) and per-protocol (PP) analyses were performed.

RESULTS

Groups were comparable at baseline. The ITT and PP eradication rates were 85.0% (95% confidence interval [CI] 75.8-94.2%) and 86.4% (95% CI 77.4-95.5%), respectively, with VA-dual therapy and 82.0% (95% CI 76.0%-87.9%) and 84.1% (95% CI 78.3-89.8%), respectively, with VAC-triple therapy. VA-dual therapy was non-inferior to VAC-triple therapy (ITT, p = 0.018; PP, p = 0.020). The adverse event rate was 10.0% with VA-dual therapy and 19.8% with VAC-triple therapy (p = 0.108).

CONCLUSIONS

The effectiveness of VA-dual therapy was comparable to that of VAC-triple therapy in H. pylori treatment-naïve junior high school students, while reducing the use of antibiotics.

Reduced Intravenous Fluorescein Dose for Upper and Lower Gastrointestinal Tract Probe-Based Confocal Laser Endomicroscopy

Background/Aims

Probe-based confocal laser endomicroscopy (pCLE) requires the administration of intravenous (IV) fluorescein. This study aimed to determine the optimal dose of IV fluorescein for both upper and lower gastrointestinal (GI) tract pCLE.

Methods

Patients 20 to 79 years old with gastric high-grade dysplasia (HGD) or colorectal neoplasms (CRNs) were enrolled in the study. The dose de-escalation method was employed with five levels. The primary endpoint of the study was the determination of the optimal dose of IV fluorescein for pCLE of the GI tract. The reduced dose was determined based on off-line reviews by three endoscopists. An insufficient dose of fluorescein was defined as the dose of fluorescein with which the pCLE images were not deemed to be visible. If all three endoscopists determined that the tissue structure was visible, the doses were de-escalated.

Results

A total of 12 patients with gastric HGD and 12 patients with CRNs were enrolled in the study. Doses were de-escalated to 0.5 mg/kg of fluorescein for both non-neoplastic duodenal and colorectal mucosa. All gastric HGD or CRNs were visible with pCLE with IV fluorescein at 0.5 mg/kg.

Conclusions

In the present study, pCLE with IV fluorescein 0.5 mg/kg was adequate to visualize the magnified structure of both the upper and lower GI tract.

Reduction in the procedure time of hybrid endoscopic submucosal dissection for early gastric neoplasms: a multi-center retrospective propensity score-matched analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) for early gastric neoplasms is still a technically difficult and time-consuming procedure. Hybrid ESD (H-ESD) involves circumferential incision with partial submucosal dissection combined with subsequent mucosal resection by snaring, wherein the newly developed device allows us to perform H-ESD using a single device. This study aimed to determine the clinical outcomes of H-ESD compared with conventional ESD (C-ESD) for early gastric neoplasms.

METHODS

In this multi-center, retrospective study, using propensity score-matched analysis, we reviewed the charts of patients with early gastric neoplasms smaller than 20 mm treated with H-ESD or C-ESD at three hospitals between January 2017 and October 2018. The primary outcome was the procedure time, and the secondary outcomes were other factors, including the en bloc resection rate, complete resection rate, curative resection rate, and rate of adverse events.

RESULTS

Among 215 patients, 29 underwent H-ESD and 186 underwent C-ESD; 29 pairs were created by propensity score matching. In the H-ESD group, 82.8% of lesions met the absolute indication [mucosal lesions limited to 20-mm diameter, dominated by differentiated adenocarcinoma without ulcer (scar)] for endoscopic resection (ER). As a result, the procedure time of H-ESD was significantly shorter than that of C-ESD [20 (interquartile range, 12-27) min versus 40 (30-50) min; p < 0.001]. There was no significant difference in the secondary outcomes between the two groups.

CONCLUSION

H-ESD contributed to reduced procedure time. Therefore, H-ESD could be an alternative endoscopic treatment for gastric neoplasms when the lesion fulfils the absolute indication for ER.

Seven-day vonoprazan and low-dose amoxicillin dual therapy as first-line Helicobacter pylori treatment: a multicentre randomised trial in Japan

OBJECTIVE

To date, no randomised trials have compared the efficacy of vonoprazan and amoxicillin dual therapy with other standard regimens for Helicobacter pylori treatment. This study aimed to investigate the efficacy of the 7-day vonoprazan and low-dose amoxicillin dual therapy as a first-line H. pylori treatment, and compared this with vonoprazan-based triple therapy.

DESIGN

This prospective, randomised clinical trial was performed at seven Japanese institutions. Patients with H. pylori-positive culture test and naive to treatment were randomly assigned in a 1:1 ratio to either VA-dual therapy (vonoprazan 20 mg+amoxicillin 750 mg twice/day) or VAC-triple therapy (vonoprazan 20 mg+amoxicillin 750 mg+clarithromycin 200 mg twice/day) for 7 days, with stratification by age, sex, H. pylori antimicrobial resistance and institution. Eradication success was evaluated by ¹³C-urea breath test at least 4 weeks after treatment.

RESULTS

Between October 2018 and June 2019, 629 subjects were screened and 335 were randomised. The eradication rates of VA-dual and VAC-triple therapies were 84.5% and 89.2% (p=0.203) by intention-to-treat analysis, respectively, and 87.1% and 90.2% (p=0.372) by per-protocol analysis, respectively. VA-dual was non-inferior to VAC-triple in the per-protocol analysis. The eradication rates in strains resistant to clarithromycin for VA-dual were significantly higher than those for VAC-triple (92.3% vs 76.2%; p=0.048). The incidence of adverse events was equal between groups.

CONCLUSION

The 7-day vonoprazan and low-dose amoxicillin dual therapy provided acceptable H. pylori eradication rates and a similar effect to vonoprazan-based triple therapy in regions with high clarithromycin resistance.

TRIAL REGISTRATION NUMBER

UMIN000034140.

The effect of scissor-type versus non-scissor-type knives on the technical outcomes in endoscopic submucosal dissection for superficial esophageal cancer: a multi-center retrospective study

The Clutch Cutter was invented as a scissor-type knife for endoscopic submucosal dissection (ESD) of gastrointestinal neoplasms. ESD with the scissor-type knife (ESD-S) may be considered a technically easier procedure than ESD with non-scissor-type knives (ESD-NS). Therefore, this study aimed to compare the technical outcomes of ESD-S with those of ESD-NS for superficial esophageal cancer. This was a multicenter retrospective study. Patients with superficial esophageal cancer treated with ESD between October 2015 and March 2018 at three hospitals were retrospectively reviewed. The ESD-S group had 48 patients and the ESD-NS group had 114 patients. A propensity score matching analysis was performed to compensate for the confounding bias between both groups. Multivariate analyses and propensity score matching were used to adjust for age, sex, the tumor size, tumor location, tumor depth, degree of tumor circumference, operator level, usage of the traction method, and the sedation method. The primary outcome was the procedure time of the ESD. Secondary outcomes were the rate of en-bloc/complete resection and the rate of complications including perforation, delayed bleeding, and stricture. Propensity score matching analysis provided 36 matched pairs. Median procedure time in the ESD-S group was significantly shorter than that in the ESD-NS group (44.0 min vs. 66.5 min, P = 0.020). In addition, the treatment outcomes were similar in both groups (en-bloc resection: 100% vs. 97.2%, P = 1; complete resection: 88.9% vs. 86.1%, P = 1; curative resection: 80.6% vs. 77.8%, P = 1; perforation: 0% vs. 5.6%, P = 0.49; delayed bleeding: 0% in both groups; stricture: 2.8% vs. 8.3%, P = 0.61). ESD-S was associated with a shorter procedure time than ESD-NS, without an increase in the incidence of complications. Therefore, the scissor-type knife should be considered as an endo-knife for ESD of superficial esophageal cancers.

Effectiveness and safety of sedation in gastrointestinal endoscopy: An opinion review

Although endoscopy is a less invasive procedure than surgery, patients can experience pain without sedation. Patients expect reduced pain during endoscopies from effective and safe sedatives. Midazolam and propofol are used for endoscopic sedation in many countries and regions. Midazolam is a widely available benzodiazepine, and many clinical trials have shown it to be an effective sedative. However, patients who are sedated with midazolam require rest in the recovery room due to its relatively long half-life, and an antagonist such as flumazenil may need to be administered in cases of deep or prolonged sedation. Propofol is a short-acting sedative with a short half-life and a quick recovery time. Therefore, the use of propofol has been increasing. However, propofol has a narrow margin of safety and often induces adverse effects such as respiratory depression. Also, propofol has no specific antagonist, and should be administered by an anesthesiologist or an endoscopist familiar with anesthesia. Remimazolam, which is a novel ultra-short-acting benzodiazepine, has recently gained attention. Remimazolam has a short half-life and an antagonist. Both effective and safe sedation is desired in accordance with the increasing need for sedative endoscopies. Therefore, in this review each sedative is summarized.

Acute esophageal necrosis after cellulitis in an obese patient with diabetes mellitus

A 59-year-old obese Japanese man with poorly controlled type 2 diabetes mellitus presented with severe heartburn for 3 days after inguinal cellulitis and exacerbated glycemic control, without any signs of upper gastrointestinal bleeding. The patient had a high plasma glucose level (34.0 mmol/L) and was dehydrated. Emergent esophagogastroduodenoscopy showed black discoloration predominantly affecting the lower esophagus; thus, acute esophageal necrosis (AEN) was diagnosed. This black discoloration was not present on esophagogastroduodenoscopy 20 days prior to presentation, and disappeared 6 days after conservative treatment. To conclude, acute esophageal necrosis should be considered if a patient in marked hyperglycemic status presents with unendurable heartburn, even when upper gastrointestinal bleeding is not observed or recent esophagogastroduodenoscopy was unremarkable.