Gut

(Objective) In our previous research, we identified latent chronic pancreatitis in the normal tissue surrounding pancreatic cancer. We also discovered the presence of Enterococcus faecalis (E. faecalis), a type of intestinal bacterium, in the pancreatic fluid and tissue of pancreatic cancer patients, suggesting it may be one of the factors contributing to the development of latent chronic pancreatitis. In this study, we performed pathological analyses to investigate its characteristics and investigate a possibility of E. faecalis infection. (Methods) Pathological analyses were performed, using 16 cases of pancreatic cancer and intraductal papillary mucinous neoplasia (IPMN) involving lesions in the pancreas tail. The involvement of E. faecalis was investigated with immunohistochemical analysis and serological methods. (Results) All cases exhibited inflammatory changes in pancreatic tissue without a clinical diagnosis of chronic pancreatitis, along with macrophage infiltration. These changes did not significantly differ according to preoperative treatment. DNA encoding E. faecalis 16s ribosomal RNA was detected in many cases, however, a positive immunostaining to E. faecalis was observed in only a few cases. Serum capsular polysaccharide (CPS) antibody levels exceeding the mean values were observed in patients with established chronic pancreatitis, while the level was not correlated with E. faecalis immunostaining. (Conclusion) These results suggest the E. faecalis infection is involved in the early stage of the progression of chronic latent pancreatitis and the diagnostic technology incorporating novel multi-biomarkers may be useful for identifying high-risk individuals for future pancreatic cancer development.

Background: Pediatric chronic pancreatitis (CP) carries an elevated lifetime risk of pancreatic ductal adenocarcinoma (PDAC), yet the cellular and molecular mechanisms driving disease progression and early neoplastic transformation remain undefined. Methods: We performed single-nucleus RNA sequencing (snRNA-seq) on pancreatic tissue from 15 pediatric CP individuals and 6 healthy controls (HC). Findings were integrated with peripheral blood flow cytometry immunophenotyping of 8 CP and 7 HC individuals and validated by histopathological assessment. Findings: We identified 15 distinct cell populations and profound cellular remodeling in CP, including a 46% reduction in acinar cells and emergence of inflammatory fibroblasts as the dominant stromal population. Acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) populations bearing early PDAC-associated transcriptional signatures were detected in most CP samples. Cell-cell interaction analysis revealed that 68% of CP-specific ligand-receptor interactions converged on ADM and PanIN populations via ECM-integrin and inflammatory pathways. Peripheral blood flow cytometry demonstrated concordant systemic immune activation, including elevated monocyte CCR2 and CD80, increased CD69 on T cells, and upregulated ROR{gamma}t in regulatory T cells. Interpretation: This atlas defines the cellular landscape and intercellular signaling networks underlying pediatric CP, identifying inflammatory fibroblasts and early neoplastic cell states as central features. These findings provide a molecular foundation for understanding cancer risk in pediatric CP and provide a resource to prioritize studies into potential therapeutic targets and biomarkers. Funding: This work was supported by the Network for Pancreatic Organ donors with Diabetes (nPOD) and The Leona M. & Harry B. Helmsley Charitable Trust.

Background & Aims. Primary sclerosing cholangitis (PSC) is a cholestatic liver disease of unknown etiology whose prevalence varies >30-fold worldwide, peaking in Northern Europe and the U.S. Upper Midwest. This geographic distribution is not fully explained by recognized risk factors. We examine its correlation with Ixodes tick exposure. Approach & Results. PSC incidence across North America, Europe, and Oceania was compared with Lyme incidence, HLA-DRB1*03 frequency, latitude and other environmental factors. Autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) were included as controls. A U.S. analysis (MarketScan, 2018-2022; 110.7 million person-years) correlated age and sex-standardized rates against 24 exposures, including Ixodes density and tick-borne infections, using ancestry-adjusted partial correlations. Cross-country PSC incidence tracked Lyme incidence (Spearman rho = 0.71-0.87); HLA-DRB1*03, AIH, and PBC did not. Alaska Native and Greenlandic populations, high-latitude but without established human exposure to Ixodes-borne pathogens, report no PSC despite high autoimmune liver disease and IBD. In the U.S., PSC was clustered and tracked Ixodes-borne pathogen incidence (ancestry-adjusted partial r, log scale: anaplasmosis +0.50, babesiosis +0.56, Powassan virus disease +0.52; in the Northeast-Midwest block, ancestry- and latitude-adjusted r = +0.72, +0.84, and +0.78, respectively). Non-Ixodes infections (Ehrlichia chaffeensis, spotted fever, tularemia), AIH, and PBC were null-to-negative; rural, agricultural, pollution, and healthcare-access also did not correlate. Conclusions. These ecological analyses are consistent with the hypothesis that Ixodes-borne pathogen exposure may trigger PSC. These ecological data cannot establish causation; they are hypothesis-generating, yielding falsifiable predictions for case control, serologic, and animal-model studies.

Esophageal adenocarcinoma (EAC) has a poor five-year survival rate and one of the fastest-rising incidences of any cancer. The presence of dysplasia in Barrett's esophagus (BE) is the main risk factor for EAC development and guides clinical management. Unfortunately, the current histopathological diagnosis of dysplasia is unreliable, with poor inter-observer agreement, highlighting the need for novel biomarkers that can improve diagnostic accuracy. Here, we performed transcriptome profiling across the full spectrum of BE-related neoplasia in 85 samples to delineate gene expression alterations in progressively worse disease stages and identify biomarkers that could complement histopathology to improve the detection of dysplasia and EAC in endoscopic biopsy specimens. Differential gene expression and pathway analyses revealed that the most extensive transcriptional changes occurred during the transition from normal squamous (NSq) to non-dysplastic BE (NDBE), consistent with metaplastic transformation. Compared to NDBE, dysplasia was characterized by enhanced cellular growth and proliferation; upregulation of immune processes and oncogenic signaling pathways were present in EAC. Using machine learning approaches, we identified a novel five-gene panel suitable for a potential RNAseq-based diagnostic test (SLC11A1, IL36A, LUCAT1, MIR215, RNU6-954P) and performed an initial validation of this signature in an additional 51 samples. We also identified several potential novel immunohistochemical markers that may warrant further evaluation, including TREM1, CXCL5, OSM, and motilin. In summary, by delineating transcriptional changes across the full disease spectrum, this study identifies several candidate biomarkers for improving current diagnostic methods for Barrett's dysplasia and EAC.

Pancreatic ductal adenocarcinoma (PDAC) is currently the third leading cause of cancer-related deaths in the United States. Intraductal papillary mucinous neoplasms (IPMNs) are neoplastic lesions of ductal origin that seed 10-25% of PDAC. There are currently no markers that distinguish between IPMN that will remain benign and those that will progress to cancer. A heterogenous population of secretory cells, including chemosensory tuft cells and hormone-expressing enteroendocrine cells (EECs), form during metaplasia and neoplastic progression in the pancreas, but the relevance of these populations as it relates to IPMN progression is not well characterized. Here, we performed spatial transcriptomics as well as multiplex immunostaining and spatial statistics on surgically resected IPMN from 60 patients to characterize these populations in all subtypes (gastric foveolar, intestinal, pancreatobiliary) and grades (low-grade, high-grade, invasive). We found that POU2F3+ tuft-like cells, CHGA+ EECs, and a subset of pancreatic endocrine cells ([a] and {gamma} cells) were present in all types of IPMN. Further, serotonin-expressing enterochromaffin cells made up the bulk of EECs in low-grade disease. Enterochromaffin, tuft-like, and glucagon-expressing alpha cells were not evenly distributed and instead were significantly enriched in a spatial manner, which is overlooked using conventional whole tissue quantification approaches. Tuft-like cell clusters were enriched with monocytes and resident memory T cells and anti-correlated to activated fibroblasts (myCAFs, iCAFs). Overall, these secretory cell clusters may reflect clonal expansion resulting in formation of distinct stromal niches with unknown consequences for disease progression.

Background and aimsPerianal fistulizing Crohns disease (pCD) affects 20% of patients with Crohns disease (CD) and severely impacts quality of life. Current therapies fail to provide sustained relief, and the molecular underpinnings of pCD remain poorly understood. This study aimed to elucidate the molecular landscape of perianal fistulas through multiomic profiling. MethodsPaired fistula-tract and adjacent rectal mucosal biopsies were collected from 63 patients (48 with pCD, 15 with cryptoglandular fistula [CPTGL]). Longitudinal sampling generated 101 unique molecular profiles, comprising of both RNA sequencing (RNA-seq) and 16S rRNA sequencing from both tissue sites, followed by integrative multiomics and gene network analyses. ResultsUnsupervised clustering revealed three patient clusters primarily defined by host gene expression, with minimal contribution from microbial profiles. Fistulae in clusters 1 and 2 showed strong immune activation and epithelial-mesenchymal transition (EMT). In contrast, cluster 3 fistulae displayed keratinization and metabolic reprogramming resembling psoriatic skin, together with reduced JAK-STAT signalling. Cluster 3 was enriched for patients classified as TOpClass:2a, who are more suitable for surgical repair (p = 0.02). Conversely, cluster 2, characterized by rectal keratinization and EMT in both fistula and rectum, showed the highest MRI inflammatory-mass score (p = 0.02) and a greater risk of subsequent ileostomy (Kaplan-Meier; p = 0.008). An independent RNAseq dataset validated the keratinization signature in a subset of pCD fistulae. ConclusionIntegrated multiomic analysis identified distinct molecular subtypes of pCD with surgical and therapeutic relevance. These findings refine the molecular understanding of pCD and support a precision medicine approach. What You Need to Know?O_ST_ABSBACKGROUND AND CONTEXTC_ST_ABSO_LIPerianal fistulas affect 1 in 5 Crohns disease patients and have a severe negative impact on the quality of life of the patients. C_LIO_LIMost advanced IBD therapies are not efficacious for perianal Crohns disease. C_LIO_LISurgical repair is not suitable for all patients. C_LI NEW FINDINGSO_LIThis study is the first to delineate molecularly defined patient subtypes in perianal fistulizing Crohns disease. It further characterizes a psoriasis-like keratinization program in a subset of fistulas. Finally, it identifies molecular features and histological indicators that may explain-and potentially help predict-favorable surgical outcomes in selected patients C_LI LIMITATIONSO_LIFunctional and mechanistic studies will be required to further dissect the drivers and dynamics of the epithelial remodeling identified. C_LI CLINICAL RESEARCH RELEVANCEO_LIRaises the possibility of refining of existing clinical stratification using molecular markers for improved therapeutic management and outcome. C_LI BASIC RESEARCH RELEVANCEO_LIProposes keratinization as an opposing molecular process to EMT within the perianal fistula tract. C_LIO_LIIdentifies robust gene signatures associated with EMT and keratinization in the fistula for further experimental and clinical studies. C_LI

BackgroundBiliary atresia (BA) is a severe neonatal liver disease characterized by progressive fibrosis and bile duct obliteration. ObjectiveAlthough immune dysregulation is implicated in the pathogenesis of BA, the specific mechanisms driving bile duct injury remain incompletely understood. This study aimed to characterize tertiary lymphoid structures (TLSs) within extrahepatic biliary remnants (EBRs), identify their cellular mediators, and evaluate the therapeutic potential of targeting IL-21 receptor signaling. DesignWe performed integrated bulk RNA sequencing, single-cell RNA sequencing, spatial transcriptomics, multiplex immunohistochemistry, and flow cytometry on clinical samples from BA patients and non-BA cholestatic controls. TLS maturation was assessed by CD23 immunohistochemistry in EBRs from 148 BA patients and correlated with clinical parameters. Anti-IL-21R antibody treatment was evaluated in a rhesus rotavirus-induced BA mouse model, with treatment initiated on day 4 post-infection. ResultsTLSs were identified in BA EBRs with significantly higher prevalence than in matched liver tissues. Mature TLSs containing CD23 germinal centers were associated with elevated serum matrix metalloproteinase-7, more advanced hepatic fibrosis, and localized autoantibody deposition on injured bile ducts. Single-cell profiling revealed expanded CD4+ T peripheral helper (Tph) cells expressing IL-21 and CXCL13 within TLS-containing EBRs. Tph cells were enriched in peripheral blood of BA patients compared to non-BA cholestatic controls (P = 0.0025), and serum IL-21 was significantly elevated (P < 0.0001). Post-infection IL-21R blockade in the mouse model reduced jaundice incidence, improved weight gain, prevented extrahepatic biliary obstruction, and significantly improved long-term survival. ConclusionTLSs in BA extrahepatic biliary remnants harbor expanded Tph cells associated with IL-21-mediated B cell activation and bile duct injury. IL-21R blockade ameliorated disease in a murine BA model, identifying the IL-21/IL-21R axis as a potential therapeutic target warranting further investigation. Key MessagesO_ST_ABSWhat is already known on this topicC_ST_ABSImmune dysregulation contributes to biliary atresia (BA), with documented lymphocyte infiltration and defective B cell tolerance. However, the cellular mechanisms linking local immune activation to bile duct injury are unclear, and the roles of organized lymphoid structures and specific CD4 T cell subsets in orchestrating local humoral responses have not been characterized. What this study addsThis study demonstrates that mature tertiary lymphoid structures in extrahepatic biliary remnants are associated with disease severity markers and localized bile duct injury in BA. We identify T peripheral helper cells as an expanded IL-21-producing CD4 T cell population within these structures, and show that post-infection IL-21 receptor blockade prevents biliary obstruction and improves survival in a murine BA model. How this study might affect research, practice or policyThese findings identify the IL-21/IL-21R signaling axis as a candidate therapeutic target in BA warranting further preclinical and translational investigation. TLS maturation status in biliary remnants and serum autoantibody levels may serve as potential biomarkers of disease severity, meriting prospective evaluation in clinical cohorts.

Abstract Introduction: The optimal examined lymph node (ELN) count after resection for pancreatic body/tail ductal adenocarcinoma (PDAC) remains uncertain. Guidelines recommend 12-15 nodes, but the value of higher thresholds is unclear. Method: SEER patients with pancreatic body/tail PDAC undergoing resection from 2000 to 2020 were analysed. Survival-anchored ELN thresholds were assessed using log-rank cut-point search, segmented Cox analysis, adjusted restricted cubic splines, and overlap-weighted restricted mean survival time (OW-RMST). A structured synthesis of 17 studies compared threshold attainment after conventional distal pancreatectomy (DP), radical antegrade modular pancreatosplenectomy (RAMPS), and posterior/artery-first approaches. Results: Among 5107 patients, 3630 deaths occurred (71.1%). Log-rank analysis identified ELN = 12 as the optimal binary cut-point; segmented Cox analysis identified ELN = 21 as a change point (bootstrap 95% CI 6.0-35.0). Adjusted splines showed a nonlinear inverse association between ELN and mortality, with attenuation beyond approximately 21 nodes. Each 5-node increase in ELN was associated with lower mortality (HR 0.964, 95% CI 0.949-0.980; P < 0.001). At 60 months, OW-RMST gains for ELN >= 12, >= 14, and >= 21 were 2.59, 2.31, and 2.60 months. Estimated probabilities of achieving ELN >= 21 were 16.5% after conventional DP, 40.0% after RAMPS, and 82.7% after posterior/artery-first approaches, with lowest certainty for the latter. Conclusion: ELN >= 12 is a minimum quality benchmark after resection for pancreatic body/tail PDAC, whereas approximately 21 nodes may be a higher-yield target. RAMPS may improve target attainment, but survival superiority remains unproven.

Background: Each year, thousands of patients are diagnosed with gastrointestinal (GI) bleeding. Many of these patients undergo colonoscopy and are subsequently diagnosed with benign or malignant colorectal neoplasms. Aim of this study is to evaluate whether patients with cardiovascular comorbidities, many of whom are on anti-platelet or anticoagulation therapy, are more likely to be diagnosed with new benign or malignant colorectal neoplasms than patients without cardiovascular comorbidities. Methods : From the 2007-2011 NIS, 802,080 primary lower GI bleed admissions (ICD-9) were identified; 283,925 had cardiovascular comorbidities. We compared patients with vs without these comorbidities for the primary outcome of new benign or malignant colorectal neoplasms. Weighted analyses accounting for the complex survey design were performed in SAS 9.4, with trends assessed using Cochran-Armitage tests and linear regression and associations with colorectal cancer stage evaluated by multinomial logistic regression (p [&le;] 0.05). Results: Between 2007-2011, the odds of malignant colorectal neoplasms increased between 49.9% and 65.3% for patients without cardiovascular comorbidities when presenting with a lower GI bleed, compared to those with cardiovascular comorbidities. Between 2007 and 2011, the most notable and statistically significant difference was observed in 2010, when patients with cardiovascular comorbidities had 10.5% higher odds of being diagnosed with benign colorectal neoplasms than those without cardiovascular comorbidities. Conclusion: Patients presenting with a lower gastrointestinal bleed without cardiovascular comorbidities were significantly more likely to be diagnosed with malignant colorectal neoplasms than those with cardiovascular comorbidities.

Introduction Patients undergoing polypectomy at colonoscopy remain at risk of metachronous neoplasia despite surveillance guided by histopathological features. Mutational profiling of adenomas, including canonical driver mutations in APC, KRAS, and TP53, may offer additional predictive value. This study aimed to determine whether mutational status in index adenomas was associated with metachronous lesion risk. Methods The INCISE cohort included patients aged 50 to 74 years who underwent polypectomy within the Scottish Bowel Screening Programme and subsequent surveillance colonoscopy within 6 years. Targeted next-generation sequencing was performed on formalin-fixed paraffin-embedded polyps. Driver mutation frequency, tumour mutational burden (TMB), and variant allele frequency (VAF) were analysed and correlated with histopathological features and metachronous outcomes using appropriate statistical models. Results A total of 895 adenomas from 723 patients were analysed. In conventional adenomas, as the number of high-risk histopathological features (size >=10mm, villous architecture, and high-grade dysplasia) increased there was a stepwise increase in the proportion of samples with a mutation in KRAS from 13% to 51% (padj<0.001) and TP53 from 8% to 35% (padj<0.001). However, neither mutation frequency (p=0.901), nor median tumour mutation burden (TMB) (2.27 vs 2.15 mut/Mb, p=0.242), in index adenomas was associated with the development of metachronous lesions. Conclusions While classical driver mutations reflect histopathological progression within adenomas, they do not predict metachronous lesion risk post-polypectomy. Targeted mutation profiling alone is insufficient for surveillance risk stratification, highlighting the need for integrated molecular approaches in this setting.

Hirschsprung disease (HSCR) is a congenital neurodevelopmental disorder characterized by segmental aganglionosis due to impaired developmental processes of enteric neural crest cells (NCCs). Despite being the leading genetic cause of functional intestinal obstruction in early childhood, HSCR represents a paradigmatic challenge in precision medicine: its multifactorial etiology, complex gene-environment interactions and limited resolution of single-modality analyses have long hindered mechanistic understanding and therapeutic translation. Here, we applied an integrative multi-omics approach combining genetic, phenotypic, epigenomic and transcriptomic analyses of matched ganglionic and aganglionic formalin-fixed paraffin-embedded (FFPE) patient tissues, complemented by patient-specific in vitro models. Beyond established genetic contributors, our integrative approach reveals novel regulatory pathways predominantly affecting enteric NCC differentiation, with convergent evidence pointing to epigenetic dysregulation as a primary disease mechanism. Notably, we identified over 1,300 differentially methylated positions between ganglionic and aganglionic FFPE samples, with HAND2 emerging as a key candidate due to multiple hypermethylated sites and consistently reduced expression levels in aganglionic tissues and in vitro models, suggesting a potential role in HSCR pathophysiology. We propose that our multi-omics approach offers a powerful and comprehensive framework for dissecting disease mechanisms. Beyond advancing biological understanding, this strategy holds promise for paving the way for molecularly informed patient stratification and supporting the development of personalized treatment and postoperative management strategies.

Aims: Serrated lesions contribute substantially to colorectal cancer (CRC), while routine management of small distal hyperplastic polyps (HPs) assumes low risk. Surveillance guidelines nevertheless incorporate uncertainty at the HP/SSL interface and recommend shortened intervals for large serrated lesions. We tested whether fibroblast activation protein-alpha; (FAPalpha) expression by stromal fibroblasts within expert-reviewed HPs stratifies risk of subsequent neoplasia. Methods and results: In a single centre historical cohort, FAPalpha; immunohistochemistry (Abcam ab53066, 1:200) was performed on FFPE colon tissues from 64 patients (normal colon n=10; HP n=39; low grade TA n=6; high-grade TA n=4; adenocarcinoma n=5). FAPalpha positive stromal fibroblasts were quantified in 20 randomly selected fields at magnification 1000 by two blinded readers (ICC 0.93). Among 39 patients with expert reviewed index HPs and colonoscopic follow up, the endpoint was metachronous adenoma occurring in the same general colonic area as the index HP, with proximal defined as ascending colon and distal as descending colon. Follow-up colonoscopies were scheduled every 2 years for up to 10 years. ROC analysis identified an optimal threshold of [&ge;]9 FAPalpha positive fibroblasts (AUC 0.8658; sensitivity 81.25%, specificity 87.93%). FAPalpha high status (44% of HPs) was associated with shortened neoplasm free survival (log-rank p=0.0012): five-year neoplasm free survival 41% versus 91% for FAPalpha; no/low. In multivariable Cox modelling, FAPalpha high status remained independently associated with metachronous adenoma (HR 4.5, 95% CI 1.2-16.8, p=0.022). Conclusion: FAPalpha+ fibroblasts in expert-reviewed colorectal HPs identify a high-risk subgroup for metachronous adenoma, supporting stromal activation markers as a feasible pathology-anchored stratification tool.

Objectives: Incisional hernia (IH) affects 13-30% of people after abdominal surgery, resulting in substantial morbidity and costs. While clinical risk factors have been studied extensively, genomic risk for IH is incompletely understood. We aimed to evaluate the impact of polygenic risk scores (PRS) on IH risk prediction. Methods] We created and evaluated three PRS for abdominal hernia, ventral hernia and latent hernia susceptibility for prediction of IH in an institutional biobank. The primary outcome was defined as the diagnosis or repair of an IH based on ICD-9/10-CM/PCS and CPT codes. Clinical covariates included age, sex, body mass index (BMI), smoking status, index procedure type, and perioperative surgical site infection. A phenome-wide association study (PheWAS) was performed to assess clinical associations with increased PRS. We then tested the ability of the PRS to improve prediction for IH by modeling clinical covariates with and without PRS in patients who underwent abdominal surgery. Model performance was assessed using 10 iterations of 5-fold cross-validation to estimate Brier scores and area under the receiver operating characteristic curve (AUROC), which were compared using cross-model Bayesian analysis of variance. Results: In 55,809 subjects, assessed PRS was significantly associated with incisional, umbilical, and ventral hernia on PheWAS, with 1.19 greater odds of developing IH per 1-SD increase in PRS (95% CI: 1.13-1.25, P \< 0.001). Of 9,909 subjects who underwent qualifying abdominal surgery, 706 developed IH. In this cohort, the latent hernia susceptibility PRS was associated with a 16% increased hazard of developing IH per 1-SD increase (HR 1.16; 95% CI: 1.07-1.26; P \< 0.001). Compared to a predictive model using clinical covariates (Brier score = 0.047, 95% CI: 0.046-0.048; AUROC = 0.660, 95% CI: 0.653-0.666), addition of the PRS showed similar Brier score and AUROC estimates (Brier score = 0.047, 95% CI: 0.046-0.048; AUROC: 0.667, 95% CI: 0.661-0.673) at five years. Cross-model Bayesian analysis demonstrated \>99% probability of practical equivalence when trying to detect a difference of [&ge;] 0.02. Conclusion: All three PRS for hernia were independently associated with IH, suggesting that genomic factors contribute significantly to IH development. However, none of the three PRS meaningfully improved clinical IH risk prediction in patients who underwent abdominal surgery. This suggests that clinical comorbidities and surgical techniques may be equally as important as genomic architecture.

Liver cancer remains a major global health burden with high mortality and limited treatment response prediction tools. Patient-derived cancer organoids have emerged as promising preclinical models that recapitulate tumor heterogeneity; however, the biological significance of morphological diversity within established organoids remains poorly characterized in hepatocellular carcinoma (HCC). In this exploratory study, we investigated whether distinct organoid growth phenotypes reflect underlying tumor biology and correlate with clinical outcomes. We established liver cancer organoids from resected tumor tissues of 27 patients and analyzed their clinical, histological, and genomic characteristics. Organoids were classified morphologically into cystic and solid types. Whole exome sequencing (WES) was conducted on six matched tumor-organoid pairs to assess genomic fidelity. Associations between organoid establishment, growth characteristics, and clinical parameters were statistically evaluated. Progression-free survival (PFS) was analyzed using the Kaplan-Meier method and univariate Cox proportional hazards regression. Organoids were successfully established in 13 of 27 cases (48.1%). Solid-type organoids were significantly associated with shorter PFS compared to cystic types (HR = 13.91; p = 0.0039, log-rank test). Organoid establishment was more frequent in older patients (>70 years), those with HBV infection, and tumors with positive {beta}-catenin expression. WES analysis demonstrated high concordance in somatic mutation profiles and variant allele frequency distributions between tissues and corresponding organoids. In univariate Cox regression, organoid growth pattern (solid vs. cystic) showed a significant association with PFS within this exploratory cohort (p = 0.0207). Patient-derived liver cancer organoids preserved the genomic and histopathological features of the original tumors. Notably, solid morphology was associated with shorter PFS, suggesting that organoid growth phenotype may serve as a supplementary indicator of tumor biological behavior in HCC. Given the modest cohort size and the absence of multivariate analysis, these preliminary findings should be interpreted with caution and warrant further large-scale validation.

Background and AimsPerianal fistulizing Crohns disease (PFCD) is a challenging complication with poorly understood pathogenesis and limited treatment options, largely due to the lack of clinically relevant animal models. Interferon-gamma (IFN-{gamma}) signaling is hyperactivated in human PFCD. We aimed to establish mouse models recapitulating human PFCD and to evaluate IFN-{gamma} as a new therapeutic target. MethodsPerianal fistulas were established in three mouse models with concurrent Crohns disease-like intestinal inflammation: wild-type (WT) mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced proctocolitis, Il10-/-mice, and TNF{Delta}69AU/+ mice. A modified MAGNIFI-CD index was developed for longitudinal fistula assessment in mice. Transcriptomic analysis and flow cytometry were conducted on mouse fistula tissue. Re-analysis of single-cell and spatial transcriptomics of human PFCD tissues was performed. Therapeutic benefits of anti-TNF-, upadacitinib, and IFN-{gamma} pathway antagonists were evaluated in the PFCD models. ResultsAll three PFCD models sustained chronic perianal fistula tracts for at least 5 weeks after wire removal. All three models closely recapitulate the pathological and molecular features of PFCD in patients, as confirmed by clinical examination, MRI, histopathology, immunostaining, flow cytometry, and transcriptomics. IFN-{gamma} signaling emerged as a central and conserved pathway across all three mouse models and human PFCD. Targeting of the IFN-{gamma} pathway promptly improved fistula healing with mitigation of IFN-{gamma} signaling, inflammation, and epithelial-to-mesenchymal transition (EMT). Moreover, combining IFN-{gamma} and TNF- blockade demonstrated augmented therapeutic efficacy compared to anti-TNF- monotherapy. ConclusionsThese PFCD mouse models and imaging tools provide first reliable and clinically relevant platforms for mechanistic studies and therapeutic evaluation. IFN-{gamma} signaling represents a potential therapeutic target warranting clinical investigation.

Background: Histological examination of mucosal tissue in inflammatory bowel diseases (IBD) is a sensitive tool to measure disease activity, and histological remission is emerging as a potentially important treatment target. There are several existing histopathological indices, but they often encompass caveats such as not primarily having been designed to measure the degree of inflammation, encompassing subjective components with poor intra- and interindividual reproducibility, and requiring expert pathologists who are scarce, thus resulting in extended response times. Aim: To construct a new computerized, automated index to objectively measure histological disease activity in the ileal and colonic mucosa, applicable to both Crohn's disease (CD) and ulcerative colitis (UC). Materials and methods: Ileocolonic biopsies were collected from control subjects and patients with CD or UC. A group of CD patients was sampled before and after 12 weeks of anti-TNF therapy. Another group of CD and UC patients functioned as a small validation cohort. Epithelial cells, neutrophils, macrophages, and T cells were immunohistochemically stained, followed by digitalization of the color signal and computerized delineation of the epithelial and lamina propria compartments. The various immune cell types within the epithelium and the lamina propria, respectively, were enumerated, and the numbers were compared between control subjects and patients with CD or UC. Results: The numbers of neutrophils and macrophages in the epithelium, and neutrophils in the lamina propria, showed the highest sensitivity and specificity for distinguishing control-subject tissues from CD and UC tissues. These three parameters were thus chosen to construct a new index, named QiC3 1.0, that could separate tissues from control subjects and patients with CD or UC with high precision. It performed equally well in a small validation cohort of patients. The QiC3 index correlated well with previously described histopathological indices, fecal calprotectin, and endoscopic scores in UC, but showed worse correlation with endoscopic scores in CD and symptomatic scores. When applying the new index to tissues from CD patients before and after therapy, it showed good responsiveness, demonstrating a distinct amelioration in the microscopic inflammatory status that corresponded well to improvements in histopathological scores. Conclusion: We describe a new quantitative, computerized, automated, non-subjective, and response-sensitive immunohistological index (QiC3) for measuring disease activity in ileal and colonic mucosal biopsies, suitable for both CD and UC.

Background and Aims Barrett's esophagus (BE) is the principal precursor of esophageal adenocarcinoma (EAC), whose incidence has risen sharply in Western countries since the 1960s. Effective, dysplasia stratified surveillance strategies are needed to prevent progression. This study evaluated the cost effectiveness of dysplasia stratified surveillance intervals and endoscopic eradication therapy (EET) across the BE spectrum. Methods We developed an incidence-based Markov state transition model of BE progression calibrated to U.S. epidemiologic data from a healthcare sector perspective over a lifetime horizon. Four hypothetical cohorts of 50-year-old individuals with short segment BE (SSBE), nondysplastic BE (NDBE), low grade dysplasia (LGD), or high-grade dysplasia (HGD) were evaluated. Strategies included no surveillance; surveillance at 1-, 2-, 3-, 4-, 5-, or 10-year intervals; standard or AI assisted endoscopy; non endoscopic screening (sponge, breath, miRNA tests); and EET for LGD and HGD. Outcomes included costs, quality adjusted life years (QALYs), incremental cost effectiveness ratios (ICERs), net monetary benefits (NMBs), EAC cases, and EAC-related deaths. Sensitivity analyses used a willingness to pay threshold of US$100,000 per QALY. Results No surveillance was the most cost-effective strategy for SSBE and NDBE. For LGD, upfront EET was more cost effective than all surveillance strategies, with results sensitive to EAC incidence and recurrence. For HGD, EET was cost saving and yielded the greatest QALYs, with findings robust in 99.9% of simulations. EET prevented 12,614 and 44,295 EAC related deaths per 100,000 individuals with LGD and HGD, respectively. Conclusion Dysplasia-stratified management is essential for optimizing surveillance and treatment strategies in BE. Any degree of dysplasia should receive EET followed by targeted post-treatment monitoring, establishing EET as the central therapeutic pathway for dysplastic BE.

Introduction: The overlap between chronic hepatitis B (CHB) and metabolic dysfunction-associated steatotic liver disease (MASLD) is an emerging global health challenge. We investigated the impact of MASLD and metabolic comorbidity in a diverse London viral hepatitis clinic. Methods: This retrospective cross-sectional study (May 2018-Feb 2024) included adults with CHB having controlled attenuation parameter (CAP) measurements. MASLD was defined as CAP >264 dB/m plus [&ge;]1 cardiometabolic factor (CMF). We used univariable and multivariable models to examine MASLD's relationship with liver stiffness and hepatitis B viral load (HBV VL). Results: Among 323 individuals (67% male, median age 36), most were from Black (35%) or non-white British/Irish (29%) backgrounds. Overall, 64% had [&ge;]1 CMF, and 20% had MASLD. The CHB/MASLD group was significantly older (median 43 vs 35 years, p<0.001) with higher median alanine transaminase (35 vs 30 IU/L, p=0.02) and liver stiffness (5.3 vs 4.7 kPa, p<0.001). Following adjustment for covariates, MASLD remained significantly associated with liver stiffness ({beta} = 0.48 kPa, p=0.03). While univariable analysis showed significantly lower HBV VL in people with MASLD (median 54 vs 417 IU/ml, p=0.004), adjusted multivariable analysis revealed no significant association between MASLD and log10 HBV VL (p=0.2). Conclusions: Although adjusted analysis does not support an independent association between MASLD and HBV VL, the data highlight a substantial cardiometabolic burden in this CHB population and clearly link MASLD to more severe liver disease. Holistic consideration of metabolic comorbidities is crucial in comprehensive CHB management.

Background and Aims: Endoscopic artificial intelligence is commonly validated on selected single images, whereas gastric cancer interpretation requires integrating whole examinations. We developed GutCore and evaluated whether whole-case endoscopic images could be used for patient-level assessment of gastric cancer depth, biomarkers, and prognosis. Methods: GutCore was pretrained on 5.6 million de-identified endoscopic images from more than ten hospitals. We compared it with five general, medical, and endoscopy-specific foundation models using open image-level datasets and an internal tertiary-center cohort of 11,035 de-identified endoscopic examinations (2019-2023): 8,049 with early or advanced gastric cancer and 2,986 with benign gastritis or intestinal metaplasia. All examination images were aggregated for patient-level assessment of cancer status, invasion depth, molecular biomarkers, and overall survival. Results: Aggregating all stored images from each examination enabled patient-level gastric cancer assessment without selecting representative frames. GutCore achieved AUCs of 0.995 for cancer detection, 0.960 for muscularis propria invasion, and 0.804 for SM2-or-deeper invasion. Prediction of tissue-defined biomarker status was strongest for Epstein-Barr virus status and MLH1 loss (AUC, 0.831 and 0.854), with lower HER2 performance (AUC, 0.673). In the held-out advanced gastric cancer test set, GutCore-derived risk groups showed marked survival separation (log-rank P < .0001; high-risk vs low-risk hazard ratio, 13.18; 95% CI, 6.06-28.66), with stratification persisting within pathological stage II and III disease. External frame-level benchmarks showed strong performance for anatomical landmark recognition, disease grading, and segmentation. Conclusions: GutCore supported whole-case patient-level gastric cancer assessment using routinely stored endoscopic images. Further validation in independent clinical cohorts is needed to establish generalizability and clinical utility.

Background & Aims: Immune-mediated liver injury from immune checkpoint inhibitors (ILICI) is a major immune-related adverse event that limits cancer immunotherapy, yet its tissue-level immunobiology is poorly defined and its management is largely extrapolated from autoimmune hepatitis (AIH). We previously identified a tri-cellular CD8+ T cell-macrophage-hepatocyte injury niche in a murine model of ILICI; here, we tested whether this niche is recapitulated in human disease. Methods: We applied imaging mass cytometry with a 32-marker panel to liver biopsies from patients with ILICI (n = 12), AIH as a disease comparator (n = 14), and healthy controls (n = 2), profiling approximately 297,000 single cells across 144 regions of interest with spatially resolved detection of apoptosis (cleaved caspase-3, cC3) and pyroptosis (cleaved gasdermin D, cGSDMD). Results: We detected histiocyte-rich granulomas in ILICI consisting of macrophages and CD8+ T cells, including activated memory-effector subsets. Permutation-based spatial analysis identified CD8+ T cell-macrophage co-localization as the most frequent significant interaction in ILICI, organizing into integrated innate-adaptive cellular neighborhoods that concentrated cC3- and cGSDMD-positive cells. Descriptively, this contrasted with AIH, in which immune cells and stroma were more spatially compartmentalized. CD8+ T-cell and macrophage densities correlated with Ishak necroinflammation scores, jaundice, and granuloma formation. Conclusions: These findings provide the first single-cell spatial proteomic characterization of human ILICI in situ; they recapitulate the tri-cellular CD8-macrophage-hepatocyte niche we previously defined in a murine model and characterize ILICI as a spatially organized innate-adaptive inflammatory process, nominating myeloid signaling and CD8-macrophage interactions as candidate liver-directed targets to uncouple hepatotoxicity from anti-tumor immunity.