Hepatocellular carcinoma presenting only as portal venous tumor thrombosis: CT demonstration.

We describe two cases of hepatocellular carcinoma initially presenting with portal vein tumor thrombi but with no demonstrable tumor in the liver parenchyma outside the portal vein. Both patients had cirrhosis of the liver and had tumor thrombi in the main portal vein and its branches. The tumor thrombi were demonstrated on ultrasonography, CT, angiography as expanding intraluminal masses.