Hepatocellular carcinoma: correlation of CT, angiographic, and histopathologic findings.

PURPOSE

To elucidate the causes of various enhancement patterns of hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

Computed tomographic (CT) scans of 68 surgically resected HCCs (62 patients) were obtained 45 seconds and 6 minutes after administration of contrast material. These scans were compared with angiographic and histopathologic findings.

RESULTS

On the early images, 24 HCCs (35%) were hypoattenuating, 33 were totally or partially hyperattenuating (48%), and 11 were isoattenuating (16%) compared to adjacent liver. On the delayed images, 55 HCCs (81%) were hypoattenuating and 13 (19%) were isoattenuating. Twenty-nine of the 48 very hypervascular or hypervascular tumors (60%) were hyperattenuating or partially hyperattenuating at early CT. Sixteen of the 20 slightly hypervascular or hypovascular tumors (80%) were isoattenuating or hypoattenuating.

CONCLUSION

Although there was relatively good agreement between tumor vascularity and enhancement pattern (60% correlation for hypervascular tumors, 80% correlation for hypovascular tumors), hyperattenuation of the large HCCs (> or = 5 cm) at CT appeared to be a function of dilated sinusoids within the tumor (peliotic changes) as well as vascularity. In patients with advanced cirrhosis, hypovascular HCCs could be hyperattenuating at CT.