The value of histological analysis of occluded biliary endoprostheses.

Abstract

Histological diagnosis of biliary strictures remains unsatisfactory, despite the availability of various endoscopic sampling procedures. The aim of our study was to assess the potential diagnostic yield of histological processing of occluded biliary endoprostheses inserted for palliation of malignant biliary stenoses. Over a period of one year, we prospectively collected biliary endoprostheses at the time of stent removal due to stent obstruction. Thirty-nine stents, inserted a mean of 94 days earlier for presumed malignant biliary strictures, were recovered. Their contents were examined histologically by two independent pathologists. Malignancy was found in 14 of 36 patients (39%). The sensitivity was highest in gallbladder carcinoma (66%), followed by choledochal and ampullary carcinoma (50%), metastatic carcinoma (33%), and pancreatic carcinoma (25%). The specificity of the method was 100%. We advocate systematic histological or cytological examination, or both, of occluded biliary endoprostheses, since the technique is of low invasiveness, has low costs, and is easy to perform, especially if other methods of tissue diagnosis have failed.