Hyperplastic liver nodules associated with early-stage primary biliary cirrhosis mimicking hepatocellular carcinoma

Nodular regenerative hyperplasia (NRH) of the liver is a condition characterized by diffuse nodular hepatocyte hyperplasia or regeneration in the absence of significant fibrous tissue deposition (1-3). NRH has been reported in association with various conditions, especially autoimmune and collagen vascular diseases, hematological disorders, and immunosuppressive therapy (2, 4-6), but its exact etiology and pathogenesis remain largely unknown. Several authors have reported on the pathologic features of hyperplastic nodules, including NRH, from patients in the early stage of primary biliary cirrhosis (PBC) (7-9). Various ultrasonographic, computed tomographic, magnetic resonance imaging, and angiographic studies of NRH have been performed (10-16), but the detailed imaging characteristics of NRH are still unclear and those of NRH associated with PBC have not been previously reported. Here we report a case of hyperplastic nodules associated with PBC, which showed a pseudotumoral pattern on helical-dynamic computed tomography (CT), angiography, CT arteriography, and CT arterial portgraphy.