[Detection of HBV DNA in hepatocellular carcinoma by in situ hybridization using a biotin-labelled probe]

Eight cases of hepatocellular carcinoma were hybridized in situ with a biotin-labelled HBV DNA probe on formalin fixed paraffin embedded sections. HBV DNA was detected in 218 cases both in cancer and pericancerous tissue of the liver, and both carcinomas were well differentiated. In three cases, HBV DNA was only present in pericancerous tissue and no HBV DNA could be identified in the remaining three cases. The positive rate of HBV DNA was 25% in tumor and 62.5% in the pericancerous area of liver. HBcAg was negative in all the eight tumors, nevertheless, HBsAg was present in one case. Both HBsAg and HBcAg were positive in the peri-cancerous tissue of liver in 6 out of 8 cases. In the remaining two, one was only HBsAg positive while the other was HBcAg positive. HBV DNA was identified mainly in the cytoplasm of tumor cells. In certain cells it was seen in the perinuclear cytoplasm or beneath the nuclear envelope. Only in a few cells, HBV DNA was distributed in the nuclei diffusely. Since HBV DNA was present both in the cytoplasm and nuclei, suggesting that HBV DNA was present in either integrated or free forms.