Cholangiocarcinoma: imaging by MR.

Magnetic resonance (MR) images and computed tomographic (CT) scans of nine patients with histologically proved cholangiocarcinoma were compared retrospectively to assess the potential of MR imaging in the detection and staging of the disease. Cholangiocarcinomas were demonstrated as soft-tissue masses by both techniques in seven of the nine patients. In three patients, the masses were more apparent with MR because of a greater degree of contrast between the tumor and the surrounding tissues. In all four patients with the scirrhous subtype of cholangiocarcinoma, the soft-tissue masses showed decreased signal intensity on the second spin-echo image (echo time = 56 msec). Displacement or encasement of the adjacent vessels was well demonstrated by MR. Distal extension of the tumor (hepatic metastases, regional lymphadenopathy) appeared on both MR images and CT scans but was more apparent with MR. Both MR and CT demonstrated intrahepatic bile duct dilatation, but CT demonstrated it more readily. MR appears to be an effective modality for the detection and staging of cholangiocarcinoma.