Hepatocellular carcinoma (HCC) is the commonest primary tumor of the liver; of late, its incidence has increased in the Western world. The authors report their experience with 42 patients affected with HCC; 36 cases were confirmed by fine-needle biopsy (FNAB), and 2 by surgery. All patients were studied with US and CT; 25 of them underwent color-Doppler US, and 30 angiography. In 9 patients, Lipiodol-CT was performed after hepatic arterial chemo-embolization. Thirty-six expansive and expansive-infiltrative lesions were observed, 4 infiltrative ones, and 1 neoplastic thrombosis of the portal vein with no evidence of parenchymal mass; 28 cases were multinodular in nature. US showed the primary lesion in all cases, while CT missed 2 lesions of 15 mm in diameter. In 19 of 25 cases studied with color-Doppler US, arterial pathologic signals were observed. Angiography confirmed all the primary lesions diagnosed by US in 30 patients and was found to be the most sensitive method to reveal multinodular lesions 8-15 mm phi, whereas Lipiodol-CT had higher resolution in detecting nodules up to 3 mm phi. The retrospective review of our results pointed out the capabilities of diagnostic imaging techniques in characterizing and staging HCCs--which is the reason why the role of biopsy has not been emphasized. The whole of the morphofunctional data obtained with the different techniques allowed lesion tissue characterization.