Three-dimensional Computed Tomographic Cholangiography as a Novel Diagnostic Tool for Evaluation of Bile Duct Invasion of Perihilar Cholangiocarcinoma.

Background/Aims: This study assessed the results of preoperative evaluation of ductal invasion by perihilar cholangiocarcinoma, imaged using 3-dimensional (3D) CT cholangiography compared to conventional endoscopic retrograde cholangiography (ERC) and magnetic resonance cholangiopancreatography (MRCP). Methodology: ERC, MRCP and 3D-CT cholangiography were planned in 24 patients with preoperatively diagnosed perihilar cholangiocarcinoma. Evaluations of bile duct images using each of 3 modalities were classified into 2 groups (the Visualization uncertain (VU) group and the Visualization certain and clear (VCC) group) according to the quality of biliary images. The results of pathological assessments and preoperative radiological evaluations were compared. Results: In the bile duct evaluation, the rates between the 2 groups were not significantly different across the three modalities. 3D-CT cholangiography evaluated tumour involvement most clearly in patients with obstructive jaundice (p = 0.044), and ERC evaluated biliary tree more clearly compared to MRCP or 3D-CT cholangiography in patients without obstructive jaundice (p = 0.051). For evaluation of pathological tumor invasion in the VCC group, 3D-CT cholangiography enabled a correct diagnosis in 7 of 11 patients, and R0 resection was achieved in 8 of 11 patients. Conclusions: 3D-CT cholangiography offers accurate preoperative assessment of bile duct invasion by perihilar cholangiocarcinoma, especially in patients with obstructive jaundice.