Accuracy and morphologic aspects of pancreatic and biliary duct brushings.

One hundred eight brushing cytology specimens with adequate follow-up were obtained from strictures of the biliary and pancreatic ducts. The material was classified as benign, reactive, low grade dysplasia, high grade dysplasia or adenocarcinoma. A diagnosis of carcinoma was made in 18 patients, high grade dysplasia in 12, low grade dysplasia in 6 and benign, nonneoplastic in the remaining cases. The diagnostic sensitivity for carcinoma was 44%, with a specificity of 98%. Ten of 12 patients with high grade dysplasia demonstrated other evidence of carcinoma. No complications were encountered. Brushing cytodiagnosis of extrahepatic biliary and pancreatic duct strictures appears to be a safe procedure, with high specificity but only modest sensitivity.