Mutation Profile and Fluorescence In Situ Hybridization Analyses Increase Detection of Malignancies in Biliary Strictures

Addition of FISH and mutation analyses to cytology analysis significantly increased the level of sensitivity with which we detected malignancy in biliary strictures, with 100% specificity. These techniques can be performed using standard brush samples collected during endoscopic retrograde cholangiopancreatography, with mutations detected in free DNA in supernatant fluid of samples. The tests are complementary and therefore should be used sequentially in the diagnostic evaluation of biliary strictures.