Value of endoscopic retrograde cholangiopancreatography-guided brushings in preoperative assessment of pancreaticobiliary strictures: what's new?

Brush cytology plays a prominent role in confirming the presence of extrahepatic biliary tract malignancy. However, its value is limited by its relatively low and widely variable sensitivity values. Various factors seem to influence the accuracy of cytologic diagnosis and are attributed to sampling, technical and interpretation errors. Ancillary methods, such as immunocytochemistry, flow cytometry, image analysis, fluorescence in situ hybridization (FISH) and the newly discovered method of global analysis of gene expression are helpful in resolving cases with inconclusive cytology and are vigorously investigated for their value in assessing the expression of novel tumor markers for the diagnosis and prognosis of pancreatic and bile duct carcinomas. However, their routine use in clinical practice remains in doubt. To increase the sensitivity of brush cytology and strengthen its role in the preoperative assessment of patients with pancreaticobiliary malignancies, the following are of the utmost importance: improvement of current sampling and cytopreparation techniques, introduction of a uniform system for reporting epithelial abnormalities based on strict and clearly distinct morphologic criteria for each pathologic entity and incorporation of experience and knowledge derived from standard cytologic methods and novel diagnostic technologies in clinical practice without compromising the high specificity associated with brush cytology.