Computed tomography and angiography were performed in 12 patients with hepatocellular carcinoma, all demonstrated with CT. In 11, the tumor had a lower attenuation than the liver parenchyma, in one a higher attenuation. Two patients had 2 lesions. The hepatic contour protruded in 10 patients. Angiography failed to demonstrate the tumor in 3 patients. The most common angiographic findings were arterial displacement in 8 patients and a hypervascular mass in 7.