Development of cavernous vasculatures in livers with hepatocellular carcinoma. An autopsy study.

The incidence and morphology of cavernous vasculatures in livers with hepatocellular carcinoma were examined. These vasculatures were grossly or microscopically found in 64% of 102 autopsied livers with hepatocellular carcinoma, though the incidence of grossly visible vasculatures was only 7%. These vasculatures were preferentially found within the portal tracts in the vicinity of portal veins obstructed by tumor emboli, especially in the cases with marked tumor emboli of the portal venous system. A majority of these vasculatures showed histochemical and immunohistochemical characteristics of blood vessels. Our findings suggest that these vasculatures frequently develop as collaterals of portal veins obstructed by the tumor emboli in hepatocellular carcinoma.