Gel immersion endoscopic mucosal resection for early gastric neoplasms: a multicenter case series study

Several cases have been reported that suggest the efficacy of gel immersion endoscopic mucosal resection (GI-EMR) for gastric neoplasms. However, no study has evaluated treatment outcomes of GI-EMR for gastric neoplasms. This study aimed to investigate the efficacy and safety of GI-EMR for early gastric neoplasms. Nine patients (17 lesions) undergoing gastric GI-EMR were included, with a median lesion size of 10 mm (interquartile range [IQR] 5-13 mm). All lesions were protruding or flat elevated. The median procedure time was 3 minutes (IQR 2-5) and en bloc resection was achieved in all cases. Among 15 neoplastic lesions, the R0 resection rate was 86.7% (13/15 lesions). Adverse events included immediate bleeding requiring hemostasis in two cases, which was controlled endoscopically. No delayed bleeding or perforation occurred. In conclusion, GI-EMR may be a safe and effective treatment for early, small gastric neoplasms. However, due to the small sample in the present study, further investigation is required regarding the indication for this technique.

Optimal timing of simethicone administration prior to upper endoscopy: A multicenter, single-blind, randomized controlled trial

Background and study aims Simethicone is useful as premedication for upper endoscopy because of its antifoaming effects. We aimed to evaluate the effect of timing of simethicone administration on mucosal visibility. Patients and methods In this multicenter, randomized, endoscopist-blinded study, patients scheduled for upper endoscopy were randomized to receive 40 mg simethicone at the following time points prior to the procedure: 20 to 30 minutes (early group), 0 to 10 minutes (late group) or 20 mg simethicone at both time points (split-dose group). Images were taken from nine predefined locations in the esophagus, stomach, and duodenum before endoscopic flushing. Each image was scored on mucosal visibility by three independent endoscopists on a 4-point scale (lower scores indicating better visibility), with adequate mucosal visibility defined as a score ≤ 2. Primary outcome was the percentage of patients with adequate total mucosal visibility (TMV), reached if all median subscores for each location were ≤ 2. Results A total of 386 patients were included (early group: 132; late group: 128; split-dose group: 126). Percentages of adequate TMV were 55%, 42%, and 61% in the early, late, and split-dose group, respectively ( P < 0.01). Adequate TMV was significantly higher in the split-dose group compared to the late group ( P < 0.01), but not compared to the early group ( P = 0.29). Differences between groups were largest in the stomach, where percentages of adequate mucosal visibility were higher in the early (68% vs 53%, P = 0.03) and split-dose group (69% vs 53%, P = 0.02) compared to the late group. Conclusions Mucosal visibility can be optimized with early simethicone administration, either as a single administration or in a split-dose regimen.

Umbrella systematic review of potential quality indicators for the detection of dysplasia and cancer at upper gastrointestinal endoscopy

Background and study aims Upper gastrointestinal (UGI) endoscopy lacks established quality indicators. We conducted an umbrella systematic review of potential quality indicators for the detection of UGI cancer and dysplasia. Methods Bibliographic databases were searched up to December 2021 for systematic reviews and primary studies. Studies reporting diagnostic accuracy, detection rates or the association of endoscopy or endoscopist-related factors with UGI cancer or dysplasia detection were included. AMSTAR2 and JBI checklists were used to assess systematic review and primary study quality. Clinical heterogeneity precluded meta-analysis and findings are summarized narratively. Results Eight systematic reviews and nine primary studies were included. Image enhancement, especially narrow band imaging, had high diagnostic accuracy for dysplasia and early gastric cancer (pooled sensitivity 0.87 (95% CI 0.84-0.89) and specificity 0.97 (0.97-0.98)). Higher detection rates with longer endoscopy examination times were reported in three studies, but no difference was observed in one study. Endoscopist biopsy rate was associated with increased gastric cancer detection (odds ratio 2.5; 95% confidence interval [CI] 2.1-2.9). Early esophageal cancer (0.17% vs 0.14%, P =0.04) and gastric cancer (0.16% vs 0.12%, P =0.02) detection rates were higher with propofol sedation compared to no sedation. Endoscopies performed by trained endoscopists on dedicated Barrett's surveillance lists had higher detection rates (8% vs 3%, P <0.001). The neoplasia detection rate during diagnostic endoscopies for Barrett's esophagus was 7% (95% CI 4%-10%). Conclusions Image enhancement use, longer examination times, biopsy rate and propofol sedation are potential quality indicators for UGI endoscopy. Neoplasia detection rate and dedicated endoscopy lists are additional potential quality indicators for Barrett's esophagus.

Safety and efficacy of underwater versus conventional endoscopic mucosal resection for colorectal polyps: Systematic review and meta-analysis of RCTs

Background and study aims Conventional endoscopic mucosal resection (C-EMR) is limited by low en-bloc resection rates, especially for large (> 20 mm) lesions. Underwater EMR (U-EMR) has emerged as an alternative for colorectal polyps and is being shown to improve en-bloc resection rates. We conducted a systematic review and meta-analysis comparing the two techniques. Methods Multiple databases were searched through November 2022 for randomized controlled trials (RCTs) comparing outcomes of U-EMR and C-EMR for colorectal polyps. Meta-analysis was performed to determine pooled proportions and relative risks (RRs) of R0 and en-bloc resection, polyp recurrence, resection time, and adverse events. Results Seven RCTs with 1458 patients (U-EMR: 739, C-EMR: 719) were included. The pooled rate of en-bloc resection was significantly higher with U-EMR vs C-EMR, 70.17% (confidence interval [CI] 46.68-86.34) vs 58.14% (CI 31.59-80.68), respectively, RR 1.21 (CI 1.01-1.44). R0 resection rates were higher with U-EMR vs C-EMR, 58.1% (CI 29.75-81.9) vs 44.6% (CI 17.4-75.4), RR 1.25 (CI 0.99-1.6). For large polyps (> 20 mm), en-bloc resection rates were comparable between the two techniques, RR 1.24 (CI 0.83-1.84). Resection times were comparable between U-EMR and C-EMR, standardized mean difference -1.21 min (CI -2.57 to -0.16). Overall pooled rates of perforation, and immediate and delayed bleeding were comparable between U-EMR and C-EMR. Pooled rate of polyp recurrence at surveillance colonoscopy was significantly lower with U-EMR than with C-EMR, RR 0.62 (CI 0.41-0.94). Conclusions Colorectal U-EMR results in higher en-bloc resection and lower recurrence rates when compared to C-EMR. Both techniques have comparable resection times and safety profiles.

Performance of endoscopic submucosal dissection for undifferentiated early gastric cancer: a multicenter retrospective cohort

Background and study aims Undifferentiated early gastric cancer (UD-EGC) represents an extended indication for endoscopic submucosal dissection (ESD) based on the existing guidelines. This study evaluated the prevalence of UD-EGC recurrence after ESD, and potentially implicated risk factors. Patients and methods Data from 17 centers were collected retrospectively including demographics, endoscopic and pathological findings, and follow-up data from UD-EGC cases treated by ESD. Patients with incomplete resection or advanced disease were excluded. Descriptive statistics quantified variables and calculated the incidence of recurrence. Chi-square test was applied to assess any link between independent variables and relapse; significantly associated variables were inserted to a multivariable regression model. Results Seventy-one patients were eligible, with 2:1 female to male ratio and age of 65.8 ± 11.8 years. Mean lesion size was 33.5 ± 18.8 mm and the most frequent histological subtype was signet ring-cells UGC (2:1). Patients were followed-up every 5.6 ± 3.7 months with a mean surveillance period of 29.3 ± 15.3 months until data collection. Four patients (5.6%) developed local recurrence 8.8 ± 6.5 months post-ESD, with no lymph node or distal metastases been reported. Lesion size was not associated with recurrence ( P = 0.32), in contrast to lymphovascular and perineural invasion which were independently associated with local recurrence ( P = 0.006 and P < 0.001, respectively). Conclusions ESD could be considered as the initial step to manage UD-EGC, providing at least an "entire-lesion" biopsy to guide therapeutic strategy. When histology confirms absence of lymphovascular and perineural invasion, this modality could be therapeutic, providing low recurrence rates.