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Introduction Biliary brush cytology is an important investigation in the diagnostic work up of bile duct strictures. The BSG ERCP standards framework supports cytological evaluation of bile duct strictures at the time of ERCP. Biliary brushing has relatively higher specificity but sensitivity remains suboptimal. Recent meta-analysis on biliary brush cytology has shown a sensitivity of 45% and specificity of 99% for malignant biliary strictures. The aim of our study was to evaluate the diagnostic performance of ERCP guided brush cytology in a non-tertiary center in the UK.Methods We carried out a retrospective cohort of consecutive biliary brushings obtained during ERCP between July 2020 and July 2025 in our organization.Patients were identified from endoscopy reporting system (Medilogic) and cross-referenced with the electronic webice system and patient care records. Data collected included demographics, stricture location, cross-sectional imaging, cytological classification of brushing sample, final diagnosis and MDT outcome. For the statistical analysis, specimens were classified as positive for malignancy (C5), suspicious for malignancy (C4), atypia (C3), benign (C2) and inadequate (C1). Patients were followed up for a minimum period of 6 months following their brush cytology.Results 256 patients (55.4% males, median age of 71 years) were included. Patients with inadequate samples (n=10) and diffuse stricturing disease involving the whole CBD (n=3) were excluded. C5 samples were included as malignant in final analysis.Table 1 shows the diagnostic yield of biliary brushings (overall and based on stricture location). Looking exclusively at pancreatic cancer and cholangiocarcinoma cohort, sensitivity was 59% & 39% respectively.Our previously conducted study in our organisation between 2015 and 2019 (n=128) showed similar results (sensitivity 41% and specificity 91%) for biliary brush cytology. The sensitivity of biliary brushings in pancreatic cancer and cholangiocarcinoma were 46% and 43% respectively.Conclusion Our study shows overall comparable sensitivity and specificity as published in the literature. It also demonstrates higher sensitivity for diagnosis of pancreatic cancer compared to cholangiocarcinoma. The results are comparable to our previously conducted study. Our study demonstrates that with specialist pathological expertise and multi-disciplinary approach, biliary brush cytology remains a valuable initial investigation for the work up of biliary strictures.Abstract P335 Table 1Overall (n=243)Distal CBD stricture (n=183)Mid CBD stricture (n=11)Proximal (including hilar) [n=49]Diagnostic accuracy (%)69.549.190.957.1Sensitivity (%)49.352.944.440Specificity (%)100100100100PPV (%)100100100100Negative predictive value (%)56.742.828.540