Thorotrast-induced hepatic angiosarcoma with 39 years latency. A pathologic and immunohistochemical study.

An autopsy case of hepatic angiosarcoma which occurred in a 64-year-old man who had been examined by Thorotrast angiography 39 years previously, is reported together with the pathologic, radiologic and immunohistochemical findings. Thorotrast deposits were found in the spleen, bone marrow, right elbow joint and lymph nodes as well as the liver. The angiosarcoma was accompanied by markedly distended sinusoids with hypertrophic and hyperplastic endothelial cells, which were considered to be closely associated with angiosarcoma. The results of immunostaining indicated that only a very limited number of tumor cells and not many sinusoidal endothelial cells showed a positive staining reaction to anti-factor VIII-related antigen (anti-F VIII-RAG). On the other hand, endothelial cells lining blood vessels in the portal areas were distinctly positive for anti-F VIII-RAG. This would suggest that production of F VIII-RAG by tumor cells was dependent on the degree of cell dedifferentiation or on the heterogeneity of endothelial cells.