Advanced endoscopy meets molecular diagnosis of cholangiocarcinoma

: Cholangiocarcinoma (CCA) remains an aggressive and deadly malignancy that is often diagnosed late. Intrinsic tumor characteristics and growth pattern of cancer cells contribute to the challenges of diagnosis and chemoresistance. However, establishing an early and accurate diagnosis and in some instances identifying targetable changes have the potential to impact survival. Primary sclerosing cholangitis, a chronic cholangiopathy prodromal to the development of a minority of cholangiocarcinomas, is a particular diagnostic challenge. We present our diagnostic and theranostic approach to the initial evaluation of cholangiocarcinomas focusing on extrahepatic cholangiocarcinoma. This involves a multi-pronged approach incorporating advanced imaging, endoscopic methods, multiple approaches to tissue sampling and molecular markers. We also provide an algorithmic approach for the sequential use of these strategies.