Intrahepatic peripheral cholangiocarcinoma: CT evaluation

The purpose of our study was to evaluate the imaging features and patterns of contrast enhancement in peripheral cholangiocarcinomas with computed tomography (CT) and correlate these features with histologic findings when available.

We reviewed the CT scans of 24 patients with 25 peripheral cholangiocarcinomas proved by orthotopic liver transplantation (n = 1), liver resection (n = 7), percutaneous needle biopsy (n = 10), and fine needle aspiration biopsy (n = 6). Incremental dynamic nonhelical CT was performed in four cases and helical CT in 21 cases. Portal venous phase images were obtained in all 25 cases. Fourteen patients underwent helical CT during arterial and portal phases. Delayed images were obtained in 20 patients.

The size of the tumors ranged from 1.2 to 17 cm. Bile duct dilatation was present in 13 patients (52%), and regional lymph node enlargement was observed in six patients (24%). Retraction of the liver capsule was present in nine patients (36%). In eight patients (32%), satellite nodules were also detected. All tumors were globally hypodense during the portal phase. In 14 patients (70%), delayed images disclosed hyperattenuating tumors. Rimlike contrast enhancement was the most frequent pattern observed in either arterial (57% of patients) or portal (60% of patients) phase imaging. Portal venous encasement was seen in 10 patients (40%).

In the proper clinical setting, detection of a hypodense hepatic lesion with peripheral enhancement, biliary dilatation, and contrast enhancement on delayed images are highly suggestive of peripheral intrahepatic cholangiocarcinoma.