Journal de radiologie vol:65 issue:10 pages:665-72
A comparative study using microangiographic and histologic techniques was realized in 43 metastatic livers, totaling 109 lesions. Three different types of tumor vascularization could be recognized. In 30 lesions, residual vessels could be identified. They constitute the only vascular elements in most of the hypervascular lesions studied. On histology, these vessels corresponded to preserved hepatic arterial branches and portal radicles. 79 lesions appeared hypervascular. In 51 lesions, hypervascularity was due to tortuous irregular vessels, corresponding at microscopy to dysplastic capillaries clearly lined with endothelial cells. On the contrary, in 28 metastases, microangiographies showed amorphous contrast uptake. In these cases the contrast was found in large intercellular spaces without endothelial lining, suggesting free interstitial circulation. These observations suggest that the morphology and the dynamic of CT in liver metastases must be influenced by the arterial or portal venous nature of the different vessels. Furthermore, the extravascular diffusion should be function of the type of tumor circulation. If this circulation is confined to real vessels, diffusion will be function of the structure of the walls of these vessels. On the contrary, if the intratumoral circulation is of the free interstitial type, diffusion will be absent and mixing will occur because of the continuity of vascular and interstitial spaces.