Citations

Abstract Generative artificial intelligence (AI) is rapidly populating medical records with synthetic or partially AI-generated content, creating a feedback loop where future models are increasingly at risk of training on uncurated AI-generated data. However, the clinical consequences of this AI-generated data contamination remain unexplored. Here, we show that in the absence of mandatory human verification, this self-referential cycle drives a rapid erosion of pathological variability and diagnostic reliability of medical data at population scale. By analysing more than 800,000 synthetic data points across clinical text generation, vision–language reporting, and medical image synthesis, we find that models progressively converge toward generic phenotypes regardless of the model architectures. Specifically, rare but critical findings, including pneumothorax and effusions, vanish from the synthetic content generated by AI models, while demographic representations skew heavily toward middle-aged male phenotypes. Crucially, this degradation is masked by false diagnostic confidence. Models continue to issue reassuring reports while failing to detect life-threatening pathology, with false reassurance rates tripling to 40%. Blinded physician evaluation confirms that this decoupling of confidence and accuracy renders AI-generated documentation clinically useless after just two generations. We systematically evaluate three mitigation strategies that can be easily integrated into existing clinical workflows, finding that while synthetic volume scaling fails to prevent collapse, mixing real data with quality-aware filtering effectively preserves diversity. Ultimately, our results suggest that without policy-mandated human oversight, the deployment of generative AI threatens to degrade the very healthcare data ecosystems it relies upon.

Abstract Lung cancer is the leading cause of cancer-related deaths worldwide, and despite advances in treatment, immune suppression remains an obstacle to effective therapy. Effector CD4+ T cells (CD4+ Teff) are critical for antitumor immunity, but their function is often inhibited by regulatory T cells (Treg), which accumulate in lung tumors and mediate suppressive functions through multiple mechanisms. This suppression leads to tumor progression and poor patient outcomes. However, the mechanisms underlying Treg-mediated suppression are not fully understood. Herein, we identify the extracellular adenosine 5-triphosphate receptor P2RX7 as a key regulator of Treg function in lung tumors. In a murine lung cancer model induced by Lewis lung carcinoma cells, we found that P2RX7 enhanced the suppressive capacity of tumor-infiltrating Tregs, promoting tumor growth. In T cell–specific P2RX7-knockout (P2RX7-KO) mice, reduced Treg infiltration was accompanied by increased CD4+ Teff accumulation and improved tumor control. Treg-specific P2RX7-KO mice exhibited reduced tumor growth, confirming a Treg-intrinsic role of P2RX7. Suppression assays revealed that tumor-infiltrating wild-type Tregs had greater suppressive activity compared with P2RX7-KO Tregs, which failed to inhibit type 1 and follicular helper T–like responses. This was associated with increased tumor-specific IgG production by lung B cells in P2RX7-KO mice. We also observed that wild-type Tregs expressed higher levels of the immunosuppressive molecule CTLA-4 when compared with P2RX7-KO Tregs. Thus, we conclude that P2RX7 expression on Tregs is essential for their suppressive function in lung cancer and targeting P2RX7 may constitute a strategy to improve lung cancer treatment by alleviating Treg-mediated immune suppression.

Abstract Background Global data demonstrate an inverse relationship between hospital ileoanal pouch volume and adverse outcomes, highlighting the need for quality metrics for this technically demanding procedure.1-4 Currently, there are no standardised quality indicators to define high-quality pouch surgery. This study aimed to establish international consensus on key performance indicators (KPIs) in pouch surgery. Methods A modified Delphi process was conducted among an international, multidisciplinary panel of experts. Participants were identified through professional networks, literature review, and direct email invitation; additional participants recruited via a snowball sampling approach over one month. Candidate KPIs were generated from literature review and expert input across 5 domains. Each item was rated on a 9-point Likert scale (1 = not important, 9 = critically important); consensus was predefined as ≥ 80% of respondents rating an item 7–9. Items not reaching consensus were re-rated in a second round following anonymized group feedback. Results Round 1 included 312 participants from 37 countries. Demographics (Table 1): 53% were age 45 years, 35.2% were female, and included surgeons (68.6%) and gastroenterologists (31.1%). Most (76.6%) practice at academic or university hospitals, with a median of 11 (5–17) years in practise; 78.9% perform >1 pouchoscopy per month, and 39.5% of surgeons perform 5 pouches/year. Respondents’ regions included North America (51%), Europe (26%), Oceania (9%), Asia (6%), Latin America (4%), and the Middle East/Africa (4%). Seven (18%) countries (Denmark, Lithuania, Malaysia, Norway, United Arab Emirates, Sweden, and Switzerland) reported pouch surgery is already centralised, while 70.6% agreed pouch centralisation should be implemented. Cost/logistics and professional autonomy were the most important barriers to centralisation, whereas capacity and training exposure were least important. Overall, 37/59 (62.7%) candidate KPIs reached consensus after Round 1. The Round 2 response rate was 61%, and 2 additional KPIs reached consensus (preop ileitis and long-term risk of pouchitis). Additionally, 14 of 25 (56%) informed consent items reached consensus, and 64% of respondents felt informed consent for pouch surgery requires 2 or more office visits. Consensus items were used to populate a KPIPS Checklist (Figure 1). Conclusion Through an international Delphi process, the KPIPS study identified a consensus-derived set of key performance indicators to measure quality in pouch surgery. These quality metrics provide a foundation for benchmarking outcomes and represent a critical step towards centralization and the development of designated pouch centres of excellence to improve global standards of care for pouch patients. References: 1. Worley GHT, Fearnhead NS, Brown SR, et al. Review of current practice and outcomes following ileoanal pouch surgery: Lessons learned from the ileoanal pouch registry and the 2017 ileoanal pouch report. Colorectal Dis 2018;20:913–22. 2. Giddings HL, Yang PF, Steffens D, Solomon MJ, Ng KS. Influence of hospital-level and surgeon factors on the outcomes after ileo-anal pouch surgery for inflammatory bowel disease: Systematic review. Br J Surg 2024;111. 3. Hoang CM, Maykel JA, Davids JS, et al. Distribution of elective ileal pouch-anal anastomosis cases for ulcerative colitis: A study utilizing the university health system consortium database. J Gastrointest Surg 2020;24:2613–9. 4. Moojen TB, Visser E, Reijntjes MA, et al. One-year stoma-free survival of ileoanal pouches for uc in european centers: The miracle project. Ann Surg Open 2025;6:e596. Conflict of interest: Prof. Holubar, Stefan: No conflict of interest Soop, Mattias: No conflict of interest Poskus, Tomas: No conflict of interest Neary, Peter: No conflict of interest Uchino, Tairin: No conflict of interest Yang, Song-soo: No conflict of interest Adamina, Michel: No conflict of interest Avellaneda, Nicolas Luis: No conflict of interest Barnes, Edward: No conflict of interest Brouquet, Antoine: No conflict of interest Brown, Steven Ross: No conflict of interest De Buck Van Overstraeten, Anthony: No conflict of interest Buskens, Christianne J.: No conflict of interest Chiorean, Michael: No conflict of interest Clark, David: No conflict of interest Cohen, Benjamin: No conflict of interest El Ouali, Sara: No conflict of interest Faiz, Omar Darius: No conflict of interest Fichera, Alessandro: No conflict of interest Hahnloser, Dieter: No conflict of interest Hancock, Laura: No conflict of interest Herfarth, Hans: No conflict of interest Johnston, Michael: No conflict of interest Kayal, Maia: No conflict of interest Laharie, David: No conflict of interest Liberman, Sender: No conflict of interest Loftus, Jr, Edward: No conflict of interest Moeslein, Gabriela: No conflict of interest Myrelid, Pär: No conflict of interest Poylin, Vitaliy: No conflict of interest Qazi, Taha: No conflict of interest Raffals, Laura: No conflict of interest Rubin, David T.: No conflict of interest Spinelli, Antonino: No conflict of interest Steinhagen, Emily: No conflict of interest Tozer, Philip: No conflict of interest Verstockt, Bram: No conflict of interest Warusavitarne, Janindra: No conflict of interest Wexner, Steven: No conflict of interest Winter, Desmond: No conflict of interest

Introduction Asthma is a multifactorial disease influenced by genetic and environmental factors, including diet. The gut microbiome contributes to airway inflammation via the gut-lung axis, partly through production of short chain fatty acids (SCFAs) from bacterial fermentation of dietary fiber. We hypothesized that dietary fiber supplementation could modulate the gut microbiome and increase SCFAs in children with asthma. Methods This is a double-blind, placebo-controlled trial of children who were randomized to consume 12 g of soluble corn fiber (SCF) as a supplement to their usual daily diet (50% the recommended daily fiber intake) or placebo for 4–6 weeks ( clinicaltrials.gov NCT03673618). Dietary surveys, asthma symptom questionnaires, fecal, blood and nasal samples were collected before and after the intervention period to quantify fiber intake, asthma control, nasal and gut microbiome, and serum short chain fatty acids (SCFAs). Results Of the 20 children enrolled, 15 completed the intervention with an average adherence rate of 83%. SCFA concentrations and gut microbiome changes varied by individual and treatment group. No significant differences in gut or nasal alpha or beta diversity were observed between groups post-intervention. However, differential abundance analysis showed a trend toward increased Bifidobacterium in the SCF group compared to placebo (ANCOM-BC p = 0.0004, FDR q = 0.073). Discussion Supplementation of 50% of recommended daily fiber intake had minimal impact on asthma symptoms, the microbiome, or SCFA levels. Future studies should consider higher fiber doses, different fiber types, or targeting individuals with low baseline fiber intake to account for observed variability in microbiome and SCFA responses. Clinical Trial Registration https://clinicaltrials.gov/study/NCT03673618 , identifier NCT03673618.

ABSTRACT Background Solid organ transplant (SOT) recipients are at risk for Pneumocystis jirovecii pneumonia (PCP), yet how their clinical phenotype and outcomes compare with other immunocompromised patients without HIV remains poorly defined. Methods We conducted a multicenter retrospective cohort study of adults with proven or probable PCP from 2017 to 2025, including 95 SOT recipients and 588 non‐SOT, non‐HIV immunocompromised patients. The primary outcome was 90‐day mortality, secondary outcomes included new renal failure requiring dialysis, and 30‐day mortality. Outcomes were analyzed using inverse probability weighting (IPW) with winsorization to adjust for baseline differences. Results In unadjusted analysis, SOT recipients had lower 90‐day mortality (hazard ratio [HR]: 0.62, 95% CI 0.39–0.97, p = 0.037). After IPW with winsorization of extreme weights, SOT status remained associated with lower 90‐day mortality (HR: 0.32, 95% CI 0.13–0.76, p = 0.009), and 30‐day mortality (HR: 0.35, 95% CI: 0.14–0.92, p = 0.034). SOT recipients had higher odds of renal failure requiring dialysis in unadjusted analysis (OR: 3.49, 95% CI 1.94–6.14, p < 0.001), which persisted after IPW adjustment (OR: 1.62, 95% CI: 1.04–2.51, p = 0.032). Conclusions Despite higher rates of renal failure requiring dialysis, SOT recipients with PCP experienced significantly improved short‐ and intermediate‐term survival compared with other non‐HIV immunocompromised patients, underscoring the need for further investigation into transplant‐associated contributors to PCP outcomes.

Abstract Background Measurement of cardiac troponin (cTn) using high-sensitivity assays is recommended for the diagnosis of myocardial infarction. We determined sex-specific and uniform 99th percentile upper reference limits (URLs) using the new Elecsys® Troponin T high-sensitivity Gen 6 assay in a global, healthy reference range cohort. Methods Lithium-heparin plasma and serum samples were prospectively collected from apparently healthy individuals aged ≥20 years across 34 global sites in the United States, Europe, China, and Japan. cTnT was measured using the Troponin T high-sensitivity Gen 6 assay on the Cobas® e 801 analyzer. Exclusion criteria were defined according to the 2022 IFCC guidance. Uniform and sex-specific 99th percentile URLs and nonparametric 95% CIs were determined in plasma and serum separately and combined. Results The final study population comprised 4147 participants (52.5% female) with a median (25th–75th percentiles) age of 48.0 (33.0–59.0) years; 45.8%, 47.9%, 5.2%, and 1.1% were White, Asian, Black, and other/unknown, respectively. For sample matrices combined (n = 8294), 81.0% and 99.2% of cTnT values were above the limit of detection in females and males, respectively. Sex-specific 99th percentile URLs (95% CI) were 18 (16–23) ng/L for females and 32 (28–35) ng/L for males; the uniform 99th percentile URL was 27 (24–31) ng/L. URLs were comparable in plasma and serum samples. Conclusions This study determined sex-specific and uniform 99th percentile URLs for the Troponin T high-sensitivity Gen 6 assay that were comparable irrespective of the matrix used in a large, global, healthy reference population.

Abstract Background Intracranial mesenchymal tumors, FET::CREB fusion-positive (ICMT), show fusions involving FET RNA-binding protein family genes (EWSR1 or FUS) and CREB family of transcription factors (ATF1, CREB1, or CREM). The methylation signature(s), gene expression characteristics, and clinical behavior of this important tumor type require further characterization. Methods We study the methylation profiles of 81 ICMT cases (61 newly profiled cases and 20 cases from publicly available sources). Clinicopathologic and genomic data were recorded for each case when available. Results ICMT showed a relatively distinct methylation signature compared to related tumors. Among the 65 cases where fusion types were documented, the identified fusions included EWSR1::ATF1 (25 cases), EWSR1::CREB1 (12 cases), EWSR1::CREM (21 cases), FUS::CREM (3 cases), and SMARCA2::CREM (4 cases). We confirmed the prior description of 2 distinct subgroups of ICMT (subclasses A and B). The majority of the cases belonged to subclass A (n = 69; 85%), which showed a higher median age compared to subclass B patients (26 years vs. 15 years). Subclass B cases (n = 12; 15%) showed shorter progression-free survival (P &lt; 0.01). Gene expression analysis of ICMT showed key overexpressed markers in ICMT, with significant CREM overexpression regardless of fusion type, when compared to either meningioma alone or a larger group of CNS tumors. Conclusions This work provides further characterization of ICMT as an important CNS mesenchymal neoplasm that is prone to tumor recurrence, showing 2 prognostically relevant methylation subclasses and warranting diagnostic distinction from other epigenetically and histologically related tumors. ICMTs show substantial overexpression of the CREM gene, independent of fusion type.

Abstract INTRODUCTION The genetic basis of sporadic early‐onset Alzheimer's disease (EOAD) remains largely unknown, prompting evaluation of late‐onset Alzheimer's disease (LOAD) polygenic risk in EOAD. METHODS A LOAD polygenic score (PGS) was calculated in the Longitudinal Early‐onset Alzheimer's Disease Study (LEADS) and Alzheimer's Disease Neuroimaging Initiative (ADNI) study and tested for associations with AD risk, cognitive performance, and imaging and fluid biomarkers. RESULTS Though PGS was elevated in LOAD and EOAD, it was not a significant predictor of EOAD adjusting for APOE ε4 carrier status and was not associated with age of EOAD onset ( p = 0.106) or with cognitive performance ( p = 0.417). In LEADS, greater LOAD PGS was associated with differences in neuroimaging and fluid biomarkers, including elevated synaptosomal‐associated protein 25 (SNAP‐25) ( p = 2.3 × 10 −5 ). DISCUSSION While LOAD polygenic risk contributed minimally to EOAD onset and cognitive dysfunction, PGS association with fluid biomarkers in LEADS suggests a role for LOAD polygenic risk in EOAD pathophysiology. Highlights LOAD PGSs were elevated in both LOAD and EOAD compared to controls; however, LOAD PGS did not significantly predict EOAD risk, age at onset, or cognitive performance independent of APOE ε4 in the LEADS. Higher LOAD PGS was associated with lower amyloid PET Centiloids (less brain amyloid deposition) as well as lower CSF biomarker Aβ42 in LEADS (proxy marker suggesting higher brain amyloid deposition) in LEADS; these contradictory findings support the need for larger studies to further investigate whether LOAD PGS is associated with increased amyloid deposition in EOAD. Higher LOAD PGS was also associated with higher levels of CSF synaptosomal‐associated protein 25 (SNAP‐25), a key component of the SNARE complex, suggesting that LOAD genetic factors may contribute to dysregulation of synaptic transmission and/or pathological protein aggregation in EOAD.

Abstract Background DPYD testing can identify patients at risk for severe toxicity when a standard fluoropyrimidine antineoplastic dose is prescribed. Sequencing-based methods detect rare variants, which require classification. Methods DPYD sequencing results over a 9-year period through to 2024 were analyzed. The dataset was filtered to calculate the positive test rate for different genotyping strategies, including targeted analysis of the Association for Molecular Pathology (AMP) Tier 1 and 2 recommended alleles, and as compared to sequencing. Variant classifications based on the laboratory’s clinical protocol were compared to ClinVar classifications and designations by the Clinical Pharmacogenetics Implementation Consortium (CPIC) expert panel. Results A DPYD variant was reported in 12.79% (896/7003) of those tested, with 2.53% (170/7003) of all reports including a variant of uncertain significance. Had only AMP Tier 1 or both Tier 1 and 2 been tested, 9.30% and 9.44% of patients would have received a positive report, respectively. Among the 281 unique, non-Tier 1/Tier 2 variants encountered during sequencing, &gt;80% were not classified by the CPIC expert panel, while &gt;48% were not reported in ClinVar. Variant classifications by our laboratory and those in ClinVar were generally concordant with the CPIC expert panel, despite the lack of a standardized classification system. Conclusions While AMP Tier 1 genotyping would have identified most patients at risk for fluoropyrimidine toxicity, sequencing is more comprehensive, identifying 26% more reportable variants compared to targeted genotyping. A standard framework for pharmacogenomic variant classification could facilitate consistent variant classification and a transition from targeted genotyping to sequencing.