CT diagnosis and differentiation of intrahepatic peripheral cholangiocarcinoma

Objective:To explore CT diagnostic and differential value of of peripheral cholangiocarcinoma.Methods:CT features of 23 cases with intrahepatic cholangiocarcinoma confirmed surgically and pathologically were retrospectively reviewed. Results:On unenhanced CT,the lesions of the intrahepatic cholangiocarcinoma presented low density and the diameters of the lesions were from 2.5 cm to 8.0 cm. The lesions showed a single mass with a low density in 19 cases and multiple lesions in 4 cases. There was a dilation of intrahepatic biliary ducts in 18 cases and a hepatolithiasis in 6 cases. Atrophy of hepatic lobe was found in 9 cases. Local retraction of the liver capsule adjacent to the tumor was displayed in 6 cases. The lesions in all cases presented mild marginal enhancement in the peripheral area and linear or reticular enhancement in the central area in arterial phase and portal phase. In delayed scanning, there was a further enhancement in the lesions,the density of which was higher than that of surrounding normal tissue of the liver. Conclusion:Most of the peripheral type of cholangiocarcinoma can be diagnosed and differentiated by CT. The delayed enhancement of the lesions and the dilatation of intrahepatic biliary ducts are characteristic CT findings.