High Level of Hepatitis B Core–Related Antigen Associated With Increased Risk of Hepatocellular Carcinoma in Patients With Chronic HBV Infection of Intermediate Viral Load

Abstract

Chronic hepatitis B virus (HBV) infection is a risk factor for hepatocellular carcinoma (HCC). Serum levels of HB core-related antigen (HBcrAg) have been associated with active replication of HBV. We investigated whether HBcrAg levels are associated with development of HCC, especially in patients who do not require antiviral treatment. We collected data from 2666 adults positive for hepatitis B surface antigen (HBsAg), infected with HBV genotypes B or C, and without liver cirrhosis, who had long-term follow-up at the National Taiwan University Hospital from 1985 through 2000. None of the patients received antiviral treatment during the follow-up. Baseline levels of HBV DNA, HBsAg, and HBcrAg were determined retrospectively and participants were followed for a mean of 15.95 years. The primary end point was an association between serum level of HBcrAg and HCC development. HCC developed in 209 patients in the cohort (incidence rate, 4.91 cases/1000 person-years). We found a positive association between baseline level of HBcrAg and HCC development; HBcrAg level was an independent risk factor in multivariable analysis. In the subgroup of hepatitis B e antigen-negative patients with HBV DNA levels from 2000 to 19,999 IU/mL (intermediate viral load [IVL]) and normal levels of alanine aminotransferase, HBcrAg levels of 10 KU/mL or more identified patients at increased risk of HCC (hazard ratio, 6.29; confidence interval, 2.27-17.48). Patients with an IVL and a high level of HBcrAg had a risk for HCC that did not differ significantly from that of patients with a high viral load (≥20,000 IU/mL). Patients with an IVL but a low level ofHBcrAg had a low risk of HCC, with an annual incidence rate of0.10% (95% confidence interval, 0.04%-0.24%). In a long-term follow-up study of 2666 patients with chronic HBV infection (genotypes B or C), level of HBcrAg is an independent risk factor of HCC. Moreover, HBcrAg level of 10 KU/mL identifies patients with an IVL who are at high risk for HCC.