Comparative Efficacy of Brush Cytology and Forceps Biopsy in the Diagnosis of Malignant Biliary Strictures: A Single-Center Study in Pakistan

ABSTRACT Introduction: The accurate diagnosis of biliary strictures or narrowing of the bile duct is challenging in clinical practice. Differentiating malignant from benign strictures is critical, because these treatments differ considerably. Although noninvasive imaging techniques help identify these strictures, they do not provide definitive tissue diagnosis, making techniques such as brush cytology and forceps biopsy essential. This study aimed to address the dearth of comparative research on the diagnostic efficacy of brush cytology and forceps biopsy in Pakistan. Methods: This single-center observational study was conducted at the Pakistan Kidney and Liver Institute & Research Center (PKLI&RC), Lahore, from March 2019 to January 2023. Patients with clinically and radiologically suspected biliary strictures were included in the study. Both brush cytology and forceps biopsy samples were subjected to cytopathological analysis by blinded pathologists. Sensitivity, specificity, and predictive values were among the key metrics analyzed. Results: The study included 54 patients in the biopsy group and 89 in the brushing group. In terms of diagnostic metrics, the biopsy technique displayed a sensitivity of 65.8%, specificity of 92.3%, positive predictive value (PPV) of 96.4%, and accuracy rate of 72.2%. For the brushing technique, the sensitivity, specificity, PPV, and accuracy were 56.7 %, 93.3%, 83.1%, and 62.9%, respectively. Although both methods showed high specificity, the biopsy technique exhibited a slightly better sensitivity and overall accuracy. Conclusion: Our findings underscore the importance of the biopsy method in the accurate diagnosis of malignant biliary strictures, showing marginally superior sensitivity and overall accuracy compared to brush cytology. This knowledge can guide clinicians in Pakistan and similar settings in making informed diagnostic choices to improve patient outcomes.