Epidemiology

Hepatitis B virus genotype C linked to increased hepatocellular carcinoma risk

Last Updated: 2004-09-23 11:25:05 -0400 (Reuters Health)

By Will Boggs, MD

NEW YORK (Reuters Health) - Patients infected with hepatitis B virus (HBV) genotype C face an increased risk of hepatocellular carcinoma (HCC), compared with patients infected with HBV genotype B, according to a report in the October issue of Gut.

"The impact of viral genotype on HCC is, in fact, controversial in the literature," Dr. Henry L-Y Chan from The Chinese University of Hong Kong, Hong Kong told Reuters Health. "This is partly because of the difference in study design and partly related to the factors put into the equation. This study is the first prospective study [that takes into account] all the potential important risk factors of HCC -- age, male gender, ALT, HBe status, basal core promoter mutations, and liver cirrhosis."

Dr. Chan and colleagues sought to determine the independent risk factors for HCC in 426 Chinese patients with chronic hepatitis B.

Twenty-five patients developed HCC during follow-up ranging from 14 to 236 weeks, the authors report, for an incidence of 1502 cases per 100,000 person-years.

Age less than 40 years, male sex, the presence of clinical liver cirrhosis, basal core promoter mutations, and genotype C HBV infection were associated with the development of HCC in a univariate analysis.

In multivariate analysis, clinical liver cirrhosis was the strongest predictor of HCC development, with a 10.24 adjusted relative risk, and HBV genotype C was associated with a 2.84-fold elevated HCC risk.

Two of the cases of HCC developed in patients without clinical or histological evidence of cirrhosis, the researchers note.

Patients with genotype C HBV were more likely than those with genotype B HBV to have persistently positive or fluctuating HBeAg status and higher ALT levels and less likely to have persistently negative HBeAg.

"HBV genotype should be considered when one designs future HCC surveillance programs," Dr. Chan said. "Patients infected with genotype C HBV should be considered as a high-risk group in addition to other conventional risk factors."

"The exact mechanism for the increased carcinogenic potential of genotype C HBV is not certain," Dr. Chan added. "Several features, including increased prevalence of basal core promoter mutation, more aggressive liver disease, and delayed HBeAg seroconversion, may play a role."

Gut 2004;53:1494-1498.