Sinusoidal capillarization of human hepatocellular carcinoma: possible promotion by fibroblast growth factor

Expression of acidic and basic fibroblast growth factors (aFGF and bFGF) and von Willebrand factor (vWF) was immunohistochemically investigated in 55 nodules of human hepatocellular carcinoma (HCC), 15 nodules of adenomatous hyperplasia (AH) of the liver and 10 cirrhotic livers (LC). AH, a putative preneoplastic lesion in the cirrhotic liver, was subdivided into ordinary and atypical types: the former was characterized by little cellular and structural atypia and the latter had some atypia equivocal as to benignity and malignancy. The positive rates of FGF (aFGF and/or bFGF) were as follows: 0% in LC, 20% in AH (ordinary and atypical) and 42% in HCC, whereas the positivity of vWF was 10% in LC, 20% in ordinary AH, 30% in atypical AH and 40% in HCC. There was no correlation between the expression of FGF or vWF and the size of HCC. No correlation was also found between the positivity of FGF and that of vWF in HCC and atypical AH. While vWF was not constantly expressed in the vicinity of FGF-positive HCC cells, capillarized sinusoids were significantly more numerous in FGF-positive cases than in FGF-negative cases (p < 0.01). These data indicate that FGF may be pathogenetically linked to the multistep development of HCC in relation to sinusoidal capillarization.