Malignant hepatic tumours associated with previous exposure to Thorotrast: four cases.

This report concerns four patients in a district general hospital who died from malignant liver tumours associated with Thorotrast (thorium dioxide) deposits in the liver. Three were known to have had diagnostic angiographic studies performed 36 to 43 years previously using Thorotrast as the contrast agent. In the fourth case no previous relevant information could be obtained. There were two men and one woman with hepatocellular carcinoma and one woman with cholangiocarcinoma. In one of the hepatoma cases there was associated hypercalcaemia of malignancy. Reported latency intervals suggest that cases of Thorotrast-related hepatic malignancy may present up to the second decade of the twenty-first century.