Analysis of loss of heterozygosity and microsatellite instability in Thorotrast-induced liver angiosarcoma

Abstract

Thorotrast is the trade name for 25% colloidal suspension of radioactive 232ThO2 that naturally emits alpha particles, and was used as a radiographic contrast agent in the second World War. After intravascular injection, more than 50% of the total amount of Thorotrast is located in the liver and is known to induce liver cancers several decades after injection. The aim of this study is to investigate the loss of heterozygosity (LOH) and microsatellite instability (MSI) in Thorotrast-induced liver angiosarcoma (AS). In addition, we performed the comparison between AS and intrahepatic cholangiocarcinoma (ICC) induced by Thorotrast. We found frequent LOH at 3p, 20p and 21q in Thorotrast-induced AS and non-Thorotrast AS. MSI did not significant different between Thorotrast and non-Thorotrast AS. The frequent LOH at 8q and 13q was observed in Thorotrast-induced AS and ICC. The results of our study suggested that the carcinogenic mechanism of Thorotrast-induced AS and ICC is partly shared.