P53 IN MALIGNANT AND BENIGN LIVER-LESIONS

p53 expression was studied by immunohistochemical methods in benign an d malignant human epithelial liver lesions in 46 patients from Hungary . Positive immunostaining for p53 protein, indicating the overexpressi on or prolonged half-life of p53 protein, was detected in the nuclei o f tumour cells of seven of the 16 hepatocellular carcinomas (HCC) (44% ), including three HCC patients with hepatitis B virus infection. Immu nostaining of p53 was seen in one of the seven hepatoblastomas, none o f the 17 focal nodular hyperplasias, and none of the six hepatocellula r adenomas. The detection of p53 in a relatively high percentage of th e HCC cases in Hungary, a country in which aflatoxin contamination of the diet is rare, suggests that factors other than aflatoxin led to th e accumulation or overexpression of p53 in these patients.