Ultrastructure of human hepatocellular carcinoma.

Twelve human hepatocellular carcinomas (HCC) were studied ultramicroscopically. In the aspects of development of cytoplasmic organelles, well differentiated cancer cells were similar to the normal hepatocytes. On the other hand, poorly differentiated HCC cells contained little cytoplasmic organelle except for relatively developed rER and ribosomes. HCC cells showed not only several differentiations but also many degenerative changes, such as fatty metamorphosis, "dark" and "clear" cells, "fingerprint" formation and myelin-like figure, and the ultratructural alterations of the vessels among HCC cells could play one of the most important roles in causing these degenerative changes in human HCC cells.