Ultrastructure of a human hepatocellular carcinoma and surrounding non-neoplastic liver

Ultrastructural study of a hepatoma and surrounding normal liver revealed the following points of interest. In spite of the fact that under light microscopy this seemed to be a very well-differentiated tumor, at the ultramicroscopic level the cells showed an inability to form desmosomes, lysosomes and vascular poles. No sinusoids lined with endothelial and Kupffer cells were detected either. These features were interpreted as a failure of full differentiation and some loss of function characteristic of tumor cells. The changes in the surrounding liver parallel those seen in the livers of rats bearing subcutaneous carcinogen-induced sarcoma for in both these instances there occurs a marked increase in lysosomes, dilatation of mitochondria and the cisternae of the endoplasmic reticulum. Other interesting findings were the occurrence of giant mitochondria (2 to 5μ), monoparticulate intranuclear glycogen and many areas of focal cytoplasmic degeneration the evolution of which has been traced.