How is dx of cholangiocarcinoma?

Cholantiography (for extrahepatic) ERCP, percutaneous THC (transhep cholangiography) [sees tumor extension and sampling and therapeutic], and MRCP [extrabiliary tumor, vascular encasement, surrounding tumors, intra and extrahepatic metastasis]. Intrahepatic: >2cm: dynamic CT/ MRI Cross-sectional imaging for guiding biliary drainage, PET very specific and sensitive (if more than 1cm up to 100%) For perihilar not as much as well as lymph node metastasis. Tissue diagnosis (biopsy) is desired but difficult to obtain (new techniques like choledochoscopy/ intraductal US... can be used.