Diagnostic performance of deep-learning-based virtual chromoendoscopy in gastric neoplasms.

BACKGROUNDS: Cycle-consistent generative adversarial network (CycleGAN) is a deep neural network model that performs image-to-image translations. We generated virtual indigo carmine (IC) chromoendoscopy images of gastric neoplasms using CycleGAN and compared their diagnostic performance with that of white light endoscopy (WLE). METHODS: WLE and IC images of 176 patients with gastric neoplasms who underwent endoscopic resection were obtained. We used 1,633 images (911 WLE and 722 IC) of 146 cases in the training dataset to develop virtual IC images using CycleGAN. The remaining 30 WLE images were translated into 30 virtual IC images using the trained CycleGAN and used for validation. The lesion borders were evaluated by 118 endoscopists from 22 institutions using the 60 paired virtual IC and WLE images. The lesion area concordance rate and successful whole-lesion diagnosis were compared. RESULTS: The lesion area concordance rate based on the pathological diagnosis in virtual IC was lower than in WLE (44.1% vs. 48.5%, p < 0.01). The successful whole-lesion diagnosis was higher in the virtual IC than in WLE images; however, the difference was insignificant (28.2% vs. 26.4%, p = 0.11). Conversely, subgroup analyses revealed a significantly higher diagnosis in virtual IC than in WLE for depressed morphology (41.9% vs. 36.9%, p = 0.02), differentiated histology (27.6% vs. 24.8%, p = 0.02), smaller lesion size (42.3% vs. 38.3%, p = 0.01), and assessed by expert endoscopists (27.3% vs. 23.6%, p = 0.03). CONCLUSIONS: The diagnostic ability of virtual IC was higher for some lesions, but not completely superior to that of WLE. Adjustments are required to improve the imaging system's performance.

Endoscopic and histological risk stratification for gastric cancer using gastric intestinal metaplasia.

BACKGROUND AND AIM: Intestinal metaplasia (IM) of the gastric mucosa is strongly associated with the risk of gastric cancer (GC). This study was performed to investigate the usefulness of endoscopic and histological risk stratification for GC using IM. METHODS: This was a post-hoc analysis of a multicenter prospective study involving 10 Japanese facilities (UMINCTR000027023). The ridge/tubulovillous pattern, light blue crest (LBC), white opaque substance (WOS), endoscopic grading of gastric IM (EGGIM) score using non-magnifying image-enhanced endoscopy, and operative link on gastric IM assessment (OLGIM) were evaluated for their associations with GC risk in all patients. RESULTS: In total, 380 patients (115 with GC and 265 without GC) were analyzed. The presence of an LBC (limited to antrum: odds ratio [OR] 2.4 [95% confidence interval 1.1-5.0], extended to corpus: OR 3.6 [2.1-6.3]), the presence of WOS (limited to antrum: OR 3.0 [1.7-5.3], extended to corpus: OR 4.2 [2.1-8.2]), and histological IM (limited to antrum: OR 3.2 [1.4-7.4], extended to corpus: OR 8.5 [4.5-16.0]) were significantly associated with GC risk. Additionally, the EGGIM score (5-8 points: OR 8.8 [4.4-16.0]) and OLGIM (stage III/IV: OR 12.5 [6.1-25.8]) were useful for stratification of GC risk. The area under the receiver operating characteristic curve value for GC risk was 0.740 for OLGIM and 0.706 for EGGIM. CONCLUSIONS: The LBC, WOS, EGGIM, and OLGIM were strongly associated with GC risk in Japanese patients. This finding can be useful for GC risk assessment in daily clinical practice.

Risk stratification of synchronous gastric cancers including alcohol-related genetic polymorphisms.

BACKGROUND AND AIM: We previously identified that ever-smoking and severe gastric atrophy in pepsinogen are risk factors for synchronous gastric cancers (SGCs). This study aimed to determine the association of alcohol drinking status or alcohol-related genetic polymorphism with SGCs and also stratify their risk. METHODS: This multi-center prospective cohort study included patients who underwent endoscopic submucosal dissection for the initial early gastric cancers at 22 institutions in Japan. We evaluated the association of alcohol drinking status or alcohol dehydrogenase 1B (ADH1B) and acetaldehyde dehydrogenase 2 (ALDH2) genotypes with SGCs. We then stratified the risk of SGCs by combining prespecified two factors and risk factors identified in this study. RESULTS: Among 802 patients, 130 had SGCs. Both the ADH1B Arg and ALDH2 Lys alleles demonstrated a significant association with SGCs on multivariate analysis (odds ratio, 1.77), although alcohol drinking status showed no association. The rates of SGCs in 0-3 risk factors in the combined evaluation of three risk factors (ever-smoking, severe gastric atrophy in pepsinogen, and both the ADH1B Arg and ALDH2 Lys alleles) were 7.6%, 15.0%, 22.0%, and 32.1%, respectively. The risk significantly increased from 0 to 3 risk factors on multivariate analysis (P for trend <0.001). CONCLUSIONS: Both the ADH1B Arg and ALDH2 Lys alleles were at high risk for SGCs. The risk stratification by these three factors may be a less invasive and promising tool for predicting their risk.

A Novel Dry Simulator Model for Learning Comprehensive Endoscopic Retrograde Cholangiopancreatography/Endoscopic Sphincterotomy Procedures while Minimizing Adverse Bleeding Events (with Video).

INTRODUCTION: Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (EST) are essential skills for performing endoscopic cholangiopancreatic procedures. However, these procedures have a high incidence of adverse events, and current training predominantly relies on patient-based approaches. Herein, we aimed to develop an ERCP/EST simulator model to address the need for safer training alternatives, especially for learners with limited ERCP experience. METHODS: The model was designed to facilitate the use of actual endoscopic devices, supporting learning objectives that align with the components of the validated Bethesda ERCP Skill Assessment Tool (BESAT). BESAT focuses on skills, such as papillary alignment, maintenance of duodenoscope position, gentle and efficient cannulation, controlled sphincterotomy in the correct trajectory, and guidewire manipulation. Thirty gastroenterology trainees used the simulator between May 2022 and March 2023, and their satisfaction was assessed using a visual analog scale (VAS) and pre- and post-training questionnaires. RESULTS: The novel simulator model comprised a disposable duodenal papillary section, suitable for incision with an electrosurgical knife, alongside washable upper gastrointestinal tract and bile duct sections for repeated use. The duodenal papillary section enabled reproduction of a realistic endoscope position and the adverse bleeding events due to improper incisions. The bile duct section allowed for the reproduction of fluoroscopic-like images, enabling learners to practice guidewire guidance and insertion of other devices. Following training, the median VAS score reflecting the expectation for model learning significantly increased from 69.5 (interquartile range [IQR]: 55.5-76.5) to 85.5 (IQR: 78.0-92.0) (p < 0.01). All participants expressed a desire for repeated simulator training sessions. CONCLUSIONS: This innovative simulator could serve as a practical educational tool, particularly beneficial for novices in ERCP. It could facilitate hands-on practice with actual devices, enhancing procedural fluency and understanding of precise incisions to minimize the risk of bleeding complications during EST.

Endoscopic Features of Synchronous Multiple Early Gastric Cancers: Findings from a Nationwide Cohort.

INTRODUCTION: We investigated the factors associated with synchronous multiple early gastric cancers and determined their localization. METHODS: We analyzed 8,191 patients who underwent endoscopic submucosal dissection for early gastric cancers at 33 hospitals in Japan from November 2013 to October 2016. Background factors were compared between single-lesion (n = 7,221) and synchronous multi-lesion cases (n = 970) using univariate and multivariate analyses. We extracted cases with two synchronous lesions (n = 832) and evaluated their localization. RESULTS: Significant independent risk factors for synchronous multiple early gastric cancer were older age (≥75 years old) (odds ratio [OR] = 1.257), male sex (OR = 1.385), severe mucosal atrophy (OR = 1.400), tumor localization in the middle (OR = 1.362) or lower region (OR = 1.404), and submucosal invasion (OR = 1.528 [SM1], 1.488 [SM2]). Depressed macroscopic type (OR = 0.679) and pure undifferentiated histology OR = 0.334) were more common in single early gastric cancers. When one lesion was in the upper region, the other was more frequently located in the lesser curvature of the middle region. When one lesion was in the middle region, the other was more frequently located in the middle region or the lesser curvature of the lower region. When one lesion was in the lower region, the other was more frequently located in the lesser curvature of the middle region or the lower region. CONCLUSION: Factors associated with synchronous multiple early gastric cancer included older age, male sex, severe mucosal atrophy, tumor localization in the middle or lower region, and tumor submucosal invasion. Our findings provide useful information regarding specific areas that should be examined carefully when one lesion is detected.

Risk factors and pattern of metastatic recurrence after endoscopic resection with additional treatment for esophageal cancer.

Although esophageal cancers invading the muscularis mucosa (pT1a-MM) or submucosa (pT1b-SM) after endoscopic resection (ER) are associated with a risk of lymph node metastasis, details of metastatic recurrence after additional treatment remain unknown. We aimed to identify the risk factors for metastatic recurrence and recurrence patterns in patients receiving additional treatment after ER for esophageal cancer. Between 2006 and 2017, patients with pT1a-MM/pT1b-SM esophageal cancer who underwent ER with additional treatment (esophagectomy, chemoradiotherapy [CRT], and radiation therapy) at 21 institutions in Japan were enrolled. We evaluated the risk factors for metastatic recurrence after ER with additional treatment. Subsequently, the rate and pattern (locoregional or distant) of metastatic recurrence were investigated for each additional treatment. Of the 220 patients who received additional treatment, 57, 125, and 38 underwent esophagectomy, CRT, and radiation therapy, respectively. In the multivariate analysis, lymphatic invasion was the sole risk factor for metastatic recurrence after additional treatment (hazard ratio, 3.50; P = 0.029). Although the risk of metastatic recurrence with additional esophagectomy was similar to that with CRT (hazard ratio, 1.01; P = 0.986), the rate of locoregional recurrence tended to be higher with additional esophagectomy (80.0% (4/5) vs. 36.4% (4/11)), leading to a better prognosis in patients with metastatic recurrence after additional esophagectomy than CRT (survival rate, 80.0% (4/5) vs. 9.1% (1/11)). Patients with lymphatic invasion have a high risk of metastatic recurrence after ER with additional treatment for pT1a-MM/pT1b-SM esophageal cancer. Additional esophagectomy may result in a better prognosis after metastatic recurrence.

Is blue light imaging without magnification satisfactory as screening for esophageal squamous cell carcinoma? Post-hoc analysis of multicenter randomized controlled trial.

OBJECTIVES: Narrow light observation is currently recommended as an alternative to Lugol chromoendoscopy (LCE) to detect esophageal squamous cell carcinoma (ESCC). Studies revealed little difference in sensitivity between the two modalities in expert settings; however, these included small numbers of cases. We aimed to determine whether blue light imaging (BLI) without magnification is satisfactory for preventing misses of ESCC. METHODS: This was a post-hoc analysis of a multicenter randomized controlled trial targeting patients at high risk of ESCC in expert settings. In this study, BLI without magnification followed by LCE was performed. The evaluation parameters included: (i) the diagnostic abilities of ESCC; (ii) the endoscopic characteristics of lesions with diagnostic differences between the two modalities; and (iii) the color difference between cancerous and noncancerous areas in BLI and LCE. RESULTS: This study identified ESCC in 49 of 699 cases. Of these cases, nine (18.4%) were missed by BLI but detected by LCE. In per-patient analysis, the sensitivity of BLI was lower than that of LCE following BLI (83.7% vs. 100.0%; P = 0.013), whereas the specificity and accuracy of BLI were higher (88.2% vs. 81.2%; P < 0.001 and 87.8% vs. 82.5%; P < 0.001, respectively). No significant endoscopic characteristics were identified, but the color difference was lower in BLI than in LCE (21.4 vs. 25.1; P = 0.003). CONCLUSION: LCE following BLI outperformed BLI in terms of sensitivity in patients with high-risk ESCC. Therefore, LCE, in addition to BLI, would still be required in screening esophagogastroduodenoscopy even by expert endoscopists.

The Impact of Tobacco Smoking and Alcohol Consumption on the Development of Gastric Cancers.

Chronic infection of Helicobacter pylori is considered the principal cause of gastric cancers, but evidence has accumulated regarding the impact of tobacco smoking and alcohol consumption on the development of gastric cancers. Several possible mechanisms, including the activation of nicotinic acetylcholine receptors, have been proposed for smoking-induced gastric carcinogenesis. On the other hand, local acetaldehyde exposure and ethanol-induced mucosal inflammation have been proposed as the mechanisms involved in the development of gastric cancers in heavy alcohol drinkers. In addition, genetic polymorphisms are also considered to play a pivotal role in smoking-related and alcohol-related gastric carcinogenesis. In this review, we will discuss the molecular mechanisms involved in the development of gastric cancers in relation to tobacco smoking and alcohol consumption.

Evolution of Stemless Reverse Shoulder Arthroplasty: Current Indications, Outcomes, and Future Prospects.

Reverse total shoulder arthroplasty (rTSA) is increasingly being used as a reliable option for various shoulder disorders with deteriorated rotator cuff and glenohumeral joints. The stemless humerus component for shoulder arthroplasties is evolving with theoretical advantages, such as preservation of the humeral bone stock and decreased risk of periprosthetic fractures, as well as clinical research demonstrating less intraoperative blood loss, reduced surgical time, a lower rate of intraoperative fractures, and improved center of rotation restoration. In particular, for anatomical total shoulder arthroplasty (aTSA), the utilization of stemless humeral implants is gaining consensus in younger patients. The current systematic review of 14 clinical studies (637 shoulders) demonstrated the clinical outcomes of stemless rTSA. Regarding shoulder function, the mean Constant-Murley Score (CS) improved from 28.3 preoperatively to 62.8 postoperatively. The pooled overall complication and revision rates were 14.3% and 6.3%, respectively. In addition, recent studies have shown satisfactory outcomes with stemless rTSA relative to stemmed rTSA. Therefore, shoulder surgeons may consider adopting stemless rTSA, especially in patients with sufficient bone quality. However, further long-term studies comparing survivorship between stemless and stemmed rTSA are required to determine the gold standard for selecting stemless rTSA.

Interactive training with a novel simulation model for upper gastrointestinal endoscopic hemostasis improves trainee technique and confidence.

Background and study aims Endoscopic hemostasis is a life-saving procedure for gastrointestinal bleeding; however, training for it is often performed on real patients and during urgent situations that put patients at risk. Reports of simulation-based training models for endoscopic hemostasis are scarce. Herein, we developed a novel simulator called "Medical Rising STAR-Ulcer type" to practice endoscopic hemostasis with hemoclips and coagulation graspers. This study aimed to evaluate the reproducibility of the clinical difficulty of this model and the effectiveness of simulation-based training for clipping hemostasis. Patients and methods This was a prospective educational study. Fifty gastroenterology residents from Japan and Canada were recruited to participate in a simulation-based training program. The primary outcome was the success rate for clipping hemostasis. We measured differences in trainee subjective assessment scores and evaluated the co-occurrence network based on comments after training. Results The hemostasis success rate of the trainees significantly increased after instruction (64% vs. 86%, P < 0.05). The success rate for ulcers in the upper body of the stomach (59%), a high-difficulty site, was significantly lower than that for ulcers in the antrum, even after feedback and instruction. Trainee self-perceived proficiency and confidence significantly improved after simulation-based training ( P < 0.05). Co-occurrence network analysis showed that trainees valued a structured learning approach, acknowledged simulator limitations, and recognized the need for continuous skill refinement. Conclusions Our study demonstrates the potential of our simulation-based training model as a valuable tool for improving technical skills and confidence in trainees learning to perform endoscopic hemostasis.

A Case of Gastric Leiomyosarcoma Completely Resected by Endoscopic Submucosal Dissection after a Precise Preoperative Diagnosis.

A 68-year-old woman was diagnosed with leiomyosarcoma (LMS) based on preoperative biopsy of the gastric body. As tumor invasion confined to the submucosa with no breaking of the submucosal layer was confirmed on endoscopic ultrasonography (EUS), the patient underwent endoscopic submucosal dissection (ESD) for gastric LMS, resulting in complete tumor resection. No apparent recurrence was observed in the 2.5 years after treatment. This is an extremely rare case of gastric LMS that underwent ESD after a precise preoperative diagnosis, with no signs of recurrence after treatment. ESD may be an acceptable option for gastric LMS when EUS findings allow this treatment method.