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Background: Barrett's esophagus (BE) represents the only established precursor to esophageal adenocarcinoma. While endoscopic surveillance is a cornerstone of early detection, it remains limited by interobserver variability, sampling error, and variability in diagnostic yield. In recent years, artificial intelligence (AI) has emerged as a promising tool to improve the detection and characterization of neoplastic lesions in BE.

Summary: This review outlines the current landscape and future potential of AI applications in the endoscopic management of BE. Diagnostic systems employing convolutional neural networks and transformer-based architectures have achieved high performance for both lesion detection (CADe) and characterization (CADx), with several models externally validated in multicenter cohorts. The first CE-certified commercial system, CADU™, has further marked the entry of AI into clinical use. Emerging developments include AI tools for infiltration depth estimation, vessel detection during endoscopic submucosal dissection, post-therapeutic surveillance, and procedural quality assessment. Challenges related to generalizability, human-AI interaction, ethical implementation, and regulatory compliance are discussed in the context of clinical translation.

Key messages: (1) AI systems demonstrate high diagnostic accuracy and enable real-time assistance in BE surveillance. (2) In-domain pretrained models and transformer-based systems may improve robustness and adaptability. (3) Clinical applications are expanding beyond diagnostics to therapeutic guidance and posttreatment monitoring. (4) Successful implementation depends on rigorous validation, explainability, and integration into clinical workflows.

Background: Barrett's esophagus and its malignant progression to Barrett's adenocarcinoma are becoming increasingly prevalent worldwide, yet their underlying mechanisms remain incompletely understood.

Summary: The pathogenesis of Barrett's esophagus and Barrett's adenocarcinoma is multifactorial, involving environmental, genetic, and cellular factors. Chronic acid and bile reflux are well-established contributors, promoting cellular transformation in the esophageal epithelium. Obesity further exacerbates this risk, both indirectly by increasing reflux and directly via proinflammatory adipokines. Recent genetic studies have identified several genetic risk variants, with loss of p53 recognized as critical event in malignant progression. Moreover, the origin of Barrett's esophagus remains under investigation, with proposed sources including cells of esophageal submucosal glands, cells of gastric cardia, and circulating bone marrow-derived cells.

Key messages: The pathophysiological mechanisms underlying Barrett's esophagus and the development of Barrett's adenocarcinoma are still under active investigation. Understanding these mechanisms is essential for developing effective preventive and therapeutic strategies.

Background: With a 50-year delay compared to Europe and the USA, esophageal adenocarcinoma (EAC) began to increase in Japan around 2010, and it is expected to continue rising over the next few decades. This 50-year discrepancy is primarily attributable to variations in the timing of the decline in Helicobacter pylori infection rates across the two regions, with the extent of obesity in Japan also exerting an influence on the projected increase in EAC. Currently, the incidence of EAC in Japan is approximately one-tenth to one-twentieth that observed in Europe and the USA. However, ongoing monitoring is essential to assess the potential for escalation of this cancer. Accurate estimation of the incidence of EAC in Barrett's esophagus (BE), a precancerous condition of EAC, is imperative for the establishment of appropriate endoscopic surveillance for early cancer detection.

Summary: The incidence of EAC in BE is largely determined by its length. In the Japanese population, BE with a length greater than 3 centimeters exhibits a high incidence of EAC and necessitates surveillance, while BE with a length less than 1 centimeter exhibits an exceptionally low incidence of EAC and is considered to require no surveillance. The challenge lies in determining the optimal approach for addressing BE with a length of 1-3 cm, which is observed in 5-15 percent of endoscopic examinees, necessitating careful consideration due to its significance.

Key message: Since the EAC risk of BE varies greatly depending on its length, the need for surveillance and inspection intervals for BE in Japan should be defined by its length.

Background: Barrett's oesophagus (BE) is the sole established precursor to oesophageal adenocarcinoma, with striking contrasts in its epidemiology and management between the East and the West.

Summary: This review, based on a structured literature search, examines the key divergences in endoscopic management: highlighting the Western emphasis on eradication therapy using ablation techniques such as radiofrequency ablation, contrasted with the Eastern expertise in advanced resection techniques including endoscopic submucosal dissection.

Key messages: Despite improving patient outcomes, significant challenges remain, including variable surveillance protocols, controversies regarding non-dysplastic BE and low-grade dysplasia, and optimal strategies for recurrent disease. As gastroesophageal reflux disease and long-segment BE rise in prevalence in the East, and Western proficiency in endoscopic submucosal dissection grows, these once-distinct approaches are poised to converge. As these treatment paradigms align, patients and clinicians alike stand to benefit from more effective, tailored care and better long-term outcomes.

Introduction: Conventional endoscopic mucosal resection (EMR) is widely accepted for 6-20 mm superficial non-ampullary duodenal epithelial tumors (SNADETs); however, its en bloc and R0 resection rates remain suboptimal. Modified techniques, such as underwater EMR (UEMR) and cap-assisted EMR (EMRC), have been introduced to improve outcomes; nevertheless, comparative data are limited despite both techniques being increasingly utilized.

Methods: This retrospective two-center study included patients with 6-20 mm SNADETs treated with either UEMR or EMRC between April 2016 and May 2024 at Kobe University Hospital and the International Clinical Cancer Research Center. Clinicopathologic characteristics, therapeutic outcomes, and adverse events were compared. Multivariate logistic regression analysis was conducted to identify risk factors for non-R0 and piecemeal resection.

Results: A total of 155 SNADETs (51 UEMR, 104 EMRC) were included. The EMRC group achieved significantly higher R0 resection rates (86.5% vs. 62.7%; p < 0.001) and en bloc resection rates (94.2% vs. 78.4%; p = 0.003) without increasing adverse events. Multivariate analysis identified UEMR, lesion size ≥ 10 mm, anterior or lateral wall involvement as independent risk factors for non-R0 resection. Lesion size ≥10 mm was the only independent risk factor for piecemeal resection.

Conclusion: In SNADETs measuring 6-20 mm, EMRC demonstrated higher en bloc and R0 resection rates than UEMR with a comparable safety profile, suggesting EMRC may be a useful option for achieving complete resection in selected cases. Prospective studies are needed to refine techniques to minimize complications while maintaining efficacy and to clarify long-term outcomes and recurrence.

Introduction: Achalasia is an esophageal motility disorder that significantly impairs quality of life. Recently, peroral endoscopic myotomy has yielded satisfactory treatment outcomes. Although the current gold standard is esophageal high-resolution manometry (HRM), early endoscopic detection is essential for accurate diagnosis. Dilatation of the esophageal lumen during endoscopy is subjective and has not been fully evaluated. We focused on the extramural compression of the vertebrae in the esophagus, which may reflect dilatation of the esophageal lumen, named the endoscopic vertebrae sign (EVS), and examined the possibility of the EVS as a novel endoscopic finding of achalasia.

Methods: Forty-three patients were diagnosed with achalasia using HRM between July 2013 and November 2022. Five who underwent surgical treatment and one for whom esophagogram was unavailable were excluded, resulting in 37 patients in the achalasia group. Among those who underwent comprehensive medical checkups and esophagogastroduodenoscopy screening at our hospital during the same period, all age- and sex-matched individuals were randomly extracted and 74 were set as controls. The rates of EVS, endoscopic esophageal dilatation at the endoscopist's discretion, and number of visible vertebrae in a single endoscopic view were retrospectively analyzed.

Results: In the achalasia group, the proportion with EVS was 86.5%, with endoscopic esophageal dilatation at the endoscopist's discretion 76%, and the number of visible vertebrae in patients with EVS was 3.2±0.9. These findings differed significantly in controls: 9.5%, 0%, and 1.4±0.4, respectively (p<0.001).

Conclusion: EVS may be one of the endoscopic findings associated with esophageal dilatation and suggestive of achalasia.

Background: Gastric cancer (GC) has a significant impact in Asia. Delay in diagnosis and treatment leads to increased mortality and morbidity. The detection of gastric intestinal metaplasia (GIM) has the potential to be an early sign of GC, but there are controversies. Differences in GC and pre-cancerous lesions between Asians and non-Asians have also contributed to this controversy.

Summary: GIM is a risk factor for developing GC in Asian adults, with more recent meta-analyses demonstrating a 3-4 fold risk in such patients. Certain GIM subtypes are more likely to develop GC, with Asian patients appearing to have more severe, diffuse, and high-risk subtypes of GIM compared to non-Asians. As a result, most international guidelines recommend endoscopic surveillance in adults with GIM, but this review article suggests it should be targeted towards those with high-risk features. This review also highlights other factors, apart from gastric histology, which are relevant in the development of GC. Factors such as Helicobacter pylori virulence, molecular and genetic mechanisms, gut microbiota, specific dietary components, and social habits as risk factors for GC are discussed.

Key messages: GIM is a risk factor for GC in the Asian population. Surveillance in a targeted population is beneficial.

Introduction: The most frequent cause of portal hypertension is liver cirrhosis (LC). Chronic hepatitis C virus (HCV) is a major cause of death and morbidity globally because of the consequences of LC, hepatocellular carcinoma, and portal hypertension, oral direct-acting antivirals (DAAs) are the effective treatment for HCV, offering a high cure rate. A virological response is also anticipated to improve portal hypertension. The aim of the study was to assess how DAA medication affects the hemodynamics of the portal circulation in patients with cirrhosis who have been infected with HCV.

Methods: A total of 120 patients with LC linked to chronic HCV were included in this study. They received treatment using regimens based on sofosbuvir combined with daclatasvir and either ribavirin or neither. Prior to beginning therapy and 2 years later, all patients underwent the following tests: complete blood count, PCR for HCV RNA, liver and renal function, abdominal ultrasonography, and colored duplex for assessment of portal hypertension.

Results: When compared to Doppler parameters prior to treatment, there is a notable improvement in Doppler metrics following DAA therapy (p = 0.006), including portal vein (PV) diameter, portal congestive index, PV cross-sectional area, splenic vein diameter, and span. Only roughly 69 patients (or 57% of the total) showed an improvement in portal pressure, whereas the percentage of sustained virological response is 95%. Numerous characteristics, such as the existence of splenomegaly and varices, a history of bilharzias, a high degree of fibrosis, and a low platelet count prior to treatment, are linked to non-changes in portal hypertension.

Conclusion: We infer that sustained virological response in HCV related cirrhotic patients following DAAs may lead to decrease in portal hypertension after an extended period of time, as adopted from portal congestion index Doppler parameters.

The article "DYRK2 regulates epithelial-mesenchymal transition restriction in pancreatic cancer liver metastasis by inhibiting Twist" [Digestion 2024; https://doi.org/10.1159/000541039] by Hang Pan, Yin Liu, Kejiu Bao, Yulin Wang, Yuping Zhang and Lina Zhou has been retracted by the Publisher and the Editor.After peer review, the accepted, unedited manuscript was published online as Early View. The authors did not respond to our requests and communication regarding the production process of their article despite extensive attempts at contact. As the article has not been approved by the authors for publication, we cannot publish the final version. To avoid confusion for readers we are retracting the Early View accepted, unedited manuscript.The authors did not respond to correspondence about the retraction.

Background: Ulcerative colitis is a diffuse, non-specific inflammatory bowel disease of unknown etiology with recurrent relapse and remission. The mechanisms of immune-mediated inflammation as a pathogenesis of ulcerative colitis have been increasingly elucidated, leading to development of biological agents and low-molecular-weight agents that target specific molecules or disease processes.

Summary: Integrin inhibitors impede ulcerative colitis pathogenesis by selectively inhibiting integrin, an adhesion molecule expressed on leukocytes, thereby suppressing lymphocyte infiltration into gastrointestinal tissues and controlling excessive immune responses at the inflammation site: the intestinal tract.

Key message: This article describes the mechanism of integrin inhibitors' action, the usefulness and positioning of vedolizumab and carotegrast methyl, which are currently available for clinical use to treat ulcerative colitis, and the status of integrin inhibitor development.