Impact of hepatitis B virus (HBV) X gene integration in liver tissue on hepatocellular carcinoma development in serologically HBV-negative chronic hepatitis C patients

Background/Aims We analyzed hepatitis B virus (HBV) X gene integration in hepatocytes of HBV-negative, chronic hepatitis C (CH-C) patients with mild fibrosis, and prospectively followed these patients for the development of hepatocellular carcinoma (HCC). Methods The study included 39 HBV-negative CH-C patients with mild fibrosis. HBV-X integration was determined by Alu-PCR analysis of liver specimens obtained by fine-needle biopsy. Results Integration of HBV-X gene sequence into liver genome occurred in 9 of the 39 patients. Six of the 39 patients developed HCC during the 12-year follow-up period. No significant difference was found in the incidence of HCC between patients with and without HBV-X integration. However, the two patients with HBV-X integration who developed HCC did not have cirrhosis at the time when HCC was diagnosed, whereas the four patients without HBV-X integration who developed HCC did have cirrhosis. Conclusions Our findings suggest that HBV-X integration detected at the mild fibrosis stage might not indicate a high risk for HCC. HBV-X integration may be associated with HCC development in the absence of cirrhosis. However, we did not find evidence that HBV-X integration directly plays a role in hepatocarcinogenesis in CH-C patients. Further studies will be needed to clarify this point.