Recently, a lot of research has been done to test for certain markers like fluorescence in situ hybridization (FISH), digital image analysis (DIA), and quantifiable morphometric results in biliary stricture brushings. Recently, polysomy FISH has been studied as a promising marker in predicting cancer in a pancreato-biliary stricture. Many genetic, epigenetic, and protein alterations arise during pancreaticobiliary tumor process. The types of markers that have been commonly evaluated as diagnostic assays are mutations, chromosomal gains and losses, and DNA methylation alterations. However there are only a few studies in this area. Testing for these markers can help determine whether the narrowing or stricture in your bile duct is cancer or not.