Differential diagnosis and treatment of biliary strictures.

Biliary tract strictures present both diagnostic and therapeutic challenges to clinicians. Advances in imaging and endoscopic techniques have improved our ability to differentiate between benign and malignant lesions. Intraductal ultrasonography (IDUS), using an endoscopic approach, has the potential to aid in separating benign and malignant biliary lesions. In a series of 93 patients, a majority of whom had cancer, we found that IDUS had a sensitivity and specificity of 89.7% and 84%, respectively, for diagnosing biliary strictures. However, benign strictures associated with untreated autoimmune pancreatitis and/or the intrapancreatic portion of the distal common bile duct could not be easily distinguished from malignant strictures. Direct visualization of biliary mucosa using a percutaneous transhepatic endoscopic approach also helps separate benign from malignant biliary strictures. Further, the ability to obtain multiple directed biopsies using a percutaneous approach also increases diagnostic accuracy. A final advantage of the percutaneous approach is that once a suitable sized tract has been established, biliary strictures and stents can be placed. IDUS and percutaneous biliary endoscopy are promising new modalities for the diagnosis and treatment of biliary strictures.