Abstract
INTRODUCTION: Biliary strictures present diagnostic challenges, necessitating early differentiation between benign and malignant cases. This study evaluates the diagnostic value of biliary and serum carcinoembryonic antigen (SCEA, BCEA) and carbohydrate antigen 19-9 (BCA19-9, SCA19-9) to enhance diagnostic accuracy. METHODS: A single-center retrospective cohort study enrolled 268 endoscopic retrograde cholangiopancreatography-treated patients, divided into training (n = 160) and validation (n = 108) sets. Levels of SCEA/SCA19-9 and BCEA/BCA19-9 were measured, and a combined diagnostic model was developed using receiver operating characteristic analysis and logistic regression. A meta-analysis of 7 studies assessed pooled odds ratios and heterogeneity in marker detection. RESULTS: BCEA and BCA19-9 levels significantly exceeded serum levels, with the combined model achieving an area under the curve of 0.921 (training) and 0.911 (validation), sensitivity 85.0%-83.3%, and specificity 83.7%-87.0%. Meta-analysis demonstrated a pooled odds ratio of 25.65, sensitivity of 95.0%, and specificity of 83.7%. CA19-9 cutoff variations had an insignificant impact, and the model improved pre-endoscopic retrograde cholangiopancreatography diagnostic accuracy by 20.7%. DISCUSSION: BCEA and BCA19-9 exhibit superior expression levels and diagnostic efficacy in distinguishing benign and malignant biliary strictures. The multimarker model enhances diagnostic performance, suggesting the relevance of integrating serum and biliary markers for accurate differentiation. Future studies should focus on optimizing cutoff values for enhanced diagnostic precision.