Diagnostic dilemmas in biliary strictures mimicking cholangiocarcinoma

Background/Aims: Bile duct strictures may be malignant or benign. In the absence of previous biliary surgery a precise preoperative diagnosis is often difficult, in particular when a tumor mass is absent in the preoperative radiologic findings. Methodology: A review of 179 patients observed between 1982 and 2001 by the same surgical team with a preoperative diagnosis of malignant stricture of the biliary tree. A surgical procedure was performed in 153 of these cases. Results: The presence of a malignant stricture was confirmed by final pathologic examination in 32 of 38 cases (96%) in which a curative resection was performed. A final diagnosis of inflammatory stricture secondary to choledocholithiasis was made in 3 of the remaining 6 cases (4%), along with one case each of sclerosing cholangitis, granular cell tumor and Mirizzi's syndrome, respectively. Conclusions: Precise preoperative evaluation of biliary strictures can be very difficult when a tumor mass is absent. Despite the use of invasive procedures and new techniques such as magnetic resonance cholangiopancreatography, a false-positive rate of 4% may be expected. However, whenever a malignancy is not definitely excluded, biliary strictures should be treated as a cholangiocarcinoma.