Scirrhous Hepatocellular Carcinoma on Gadoxetic Acid-Enhanced Magnetic Resonance Imaging and Diffusion-Weighted Imaging: Emphasis on the Differentiation of Intrahepatic Cholangiocarcinoma

Objective: The objective of this study was to determine the features of scirrhous hepatocellular carcinoma (sHCC) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) with an emphasis on the differentiation from intrahepatic cholangiocarcinoma (ICC). Materials and Methods: A total of 41 patients with sHCCs and 41 patients with ICCs underwent gadoxetic acid-enhanced MRI and DWI. Images were analyzed for shape of lesions, surface retraction, enhancement pattern, proportion of arterial hyperenhancement, target appearance on the hepatobiliary phase and DWI, and presence of necrosis. Results: Lobulating shape, rim enhancement, and target appearance on the hepatobiliary phase and DWI were the main features in both tumors. The proportion of arterial hyperenhancement of 20% of tumor diameter or more was the only significant MRI feature for differentiating sHCC from ICC (P <= 0.006 in the multivariate analysis). Conclusions: Although the features of sHCC on gadoxetic acid-enhanced MRI and DWI are similar to those of ICC, the proportion of hyperenhancement of 20% or more on the arterial phase is a helpful feature in distinguishing sHCC from ICC.