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Introduction: Sedation protocols for balloon-assisted enteroscopy (BAE) are not yet standardized. The aim of this study was to compare efficacy and safety between continuous infusion and intermittent bolus administration of midazolam for sedation during BAE. The study hypothesis was that continuous infusion would provide a greater proportion of time under conscious sedation than would intermittent bolus administration.

Methods: We conducted a multicenter, prospective, double-blind, randomized controlled trial at 15 institutions of the National Hospital Organization in Japan. Patients scheduled for diagnostic or therapeutic BAE were randomly assigned to receive continuous infusion or intermittent bolus administration of intravenous midazolam. The primary endpoint was the proportion of time under conscious sedation, defined as a Ramsay Sedation Scale (RSS) score of 3-4. Secondary endpoints included body movements causing procedure interruption, endoscopist and patient satisfaction, total drug dosage, adverse events, and termination of the procedure.

Results: Of 76 enrolled patients (39 continuous infusion group, 37 intermittent bolus group), one from each group discontinued before treatment, leaving 74 patients (38 continuous group, 36 intermittent bolus group) for analysis. The proportion of time under conscious sedation was comparable between groups (mean±SD: 0.637±0.315 vs. 0.609±0.272, p=0.721). However, the continuous infusion group showed a lower incidence of body movements causing procedure interruption (7.9% vs. 25.0%, p=0.091). The total midazolam dose was higher in the continuous infusion group, whereas the incidence of adverse events was comparable between the two groups.

Conclusions: Continuous infusion of midazolam did not demonstrate superiority over intermittent bolus administration with regard to the proportion of time under conscious sedation. However, continuous infusion suppressed body movements during BAE without increasing adverse events; thus, it could be one of the feasible sedation options for BAE in clinical practice.

Introduction: The incidence of inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is increasing rapidly worldwide. Although multiple advanced therapies are now available, selecting the optimal treatment remains challenging due to the expanding options and diverse healthcare systems.

Methods: We conducted a questionnaire survey among physicians in nine Asian countries prior to the 18th International Gastrointestinal Consensus Symposium (IGICS) to assess the current status of advanced therapies for IBD. The survey included questions regarding therapeutic agent selection, biomarkers, and imaging modalities for monitoring.

Results: Of the 210 respondents, 173 physicians treating IBD were analyzed. Anti-TNFα antibodies remain the most commonly selected advanced therapy for both UC and CD. Elderly patients with UC were more likely to receive anti-α4β7-integrin antibodies or anti-IL-12/23p40 monoclonal antibodies, reflecting safety considerations. Janus kinase inhibitors were used more frequently as a second-line option in severe cases. Comorbidities, drug costs, and lifestyle factors also influenced treatment choice. CRP is the most common biomarker used for monitoring, and endoscopy is the most frequently used imaging modality.

Conclusion: This questionnaire survey revealed the current status of advanced therapies for IBD in nine Asian countries and regions. Region-specific evidence-based algorithms for selecting advanced therapies for IBD should be established.

Background: Barrett's esophagus (BE) is a recognized precursor to esophageal adenocarcinoma (EAC), yet its endoscopic diagnosis remains inconsistent worldwide. This review summarizes current challenges and recent advancements in the endoscopic diagnosis of BE, including updates from international consensus statements and emerging technologies such as image-enhanced endoscopy (IEE) and artificial intelligence (AI).

Summary: This narrative review integrated international guidelines, multicenter studies, expert consensuses, including the Kyoto International Consensus and Asian Barrett Consortium data, and recent trials of diagnostic imaging and quality indicators (QIs) regarding BE surveillance.

Key messages: Discrepancies in defining the gastroesophageal junction (GEJ) - notably between palisade vessels and gastric folds - contribute to the global variability of the BE diagnosis. The Kyoto International Consensus recommends using the distal end of the palisade vessels as a more stable and histologically consistent landmark. Additionally, the Prague C & M criteria offer a standardized approach to measuring the BE length; however, limitations for ultra-short-segment BE exist. IEE modalities such as linked color imaging and red dichromatic imaging enhance GEJ visualization, whereas AI systems have the potential for automated BE classification. QIs such as the neoplasia detection rate, inspection time, and adherence to biopsy protocols have been proposed to improve diagnostic consistency and outcomes. Standardizing the endoscopic definition of BE and adopting quality-based surveillance strategies are essential to improving detection and reducing variability. Incorporating IEE- and AI-based tools into routine practice may support a more reliable and efficient diagnostic pathway for BE, thus facilitating early EAC detection and prevention worldwide.

Background: Barrett's esophagus (BE)-related neoplasia remains less prevalent in Japan than in Western countries; however, its incidence is steadily rising. While multimodal treatment - typically endoscopic resection (ER) followed by ablation - is the standard of care, ER alone remains the primary treatment strategy in Japan. With advances in endoscopic techniques, endoscopic submucosal dissection (ESD) has become the mainstay for managing BE-related neoplasia. This review outlines the current Japanese approach, focusing on indications, preoperative assessment, treatment outcomes, and post-resection surveillance practices within the Japanese clinical context.

Summary: Accurate endoscopic assessment, including the use of magnifying endoscopy with image-enhanced modalities, is central to Japanese practice due to the importance of complete resection of neoplasia in the absence of ablative therapy. While data on BE-related neoplasia remain relatively limited in Japan, several multicenter studies have demonstrated favorable outcomes for ESD in terms of resection quality, safety, and long-term survival, particularly in low-risk patients. However, challenges remain, including the lack of standardized surveillance protocols and considerable heterogeneity in clinical practice across institutions. The establishment of unified clinical pathways and evidence-based strategies will be essential to address the increasing burden of BE-related neoplasia in Japan.

Key messages: The incidence of BE and esophageal adenocarcinoma is increasing in Japan, although still significantly lower than in Western countries. Unlike the Western standard of combining ER with radiofrequency ablation (RFA), Japanese practice relies primarily on ESD as the main curative modality. RFA is not widely available in Japan, leading to a reliance on complete resection and more aggressive ER strategies. Surveillance strategies remain inconsistent, largely due to the lower disease prevalence and limited Japan-specific clinical evidence.

Background: Barrett's esophagus (BE) is the replacement of normal squamous epithelium in the distal esophagus by columnar epithelium. The prognosis of esophageal adenocarcinoma depends largely on the stage at diagnosis. Advances in endoscopic imaging and quality standards have significantly improved the early detection of BE-associated neoplasia. This review summarizes current classification systems, sampling protocols, and adjunct tools for diagnosing early neoplasia in BE in Western practice.

Summary: In Western practice, the diagnosis of BE relies on consensus criteria requiring endoscopic evidence and histopathological confirmation of columnar epithelium proximal to the gastroesophageal junction. However, there are discrepancies regarding the minimum BE extent and the necessity of intestinal metaplasia for diagnosis. Detecting early neoplasia in BE is challenging due to the flat and subtle nature of dysplastic lesions. High-definition white-light endoscopy (HD-WLE) is the standard modality for BE surveillance and is used to assess for characteristic features of neoplasia, including nodularity, surface irregularity, color changes, and demarcated areas. Image-enhancing techniques - such as virtual chromoendoscopy (e.g., narrow-band imaging [NBI], texture and color enhancement imaging [TXI], blue light imaging [BLI], linked color imaging [LCI]), and acetic acid chromoendoscopy - have improved dysplasia detection when applied alongside validated classification systems. Despite technological advances, random four-quadrant biopsies (4QBs) remain the standard for dysplasia detection. Estimating lesion depth is based primarily on HD-WLE, with limited contribution from chromoendoscopy and ancillary imaging techniques (i.e., endoscopic ultrasound [EUS], confocal laser endomicroscopy, optical coherence tomography).

Key messages: Early Barrett's neoplasia is challenging to detect. HD-WLE and image-enhancing techniques improve visualization, but random 4QBs remain central to the diagnostic process. Lesion depth is primarily assessed using endoscopic features and, to a limited extent, ancillary techniques.

Background: Barrett's esophagus (BE) is becoming increasingly prevalent in both Western countries and Japan. Early diagnosis of Barrett's neoplasia remains challenging. Traditionally, the Seattle protocol, a four-quadrant random biopsy method, has been recommended in Western guidelines. However, this approach has several limitations, including sampling errors, poor adherence, and a high procedural burden. Therefore, magnifying endoscopy has gained attention as a valuable tool for detecting and characterizing neoplastic lesions in patients with BE.

Summary: This review outlines historical and current developments in magnifying endoscopic classification systems for BE, with a focus on narrow-band imaging (NBI) and acetic acid chromoendoscopy in both Western countries and Japan. Although various NBI-based classifications have been proposed, their complexity and poor reproducibility have limited their widespread clinical adoption. Recently, simplified and standardized classification systems, including the Barrett's International NBI Group classification in the West and the Japan Esophageal Society-Barrett's esophagus classification in Japan, have been introduced. These systems adopt a binary framework, categorizing mucosal and vascular patterns as "regular" (non-neoplastic) or "irregular" (neoplastic). They are easy to apply and have demonstrated high diagnostic accuracy and substantial interobserver agreement. Further simplification and practical refinement are required for broader clinical implementation.

Key messages: Compared with other gastrointestinal cancers, the magnifying endoscopic diagnosis of Barrett's neoplasia remains technically demanding. However, based on a growing body of evidence, endoscopists should be encouraged to actively challenge this area. Continued efforts to simplify and validate the classification systems are essential for their widespread clinical use in BE surveillance.

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.