Infection with a specific subtype of hepatitis B virus (HBV) and a high viral load are associated both independently and additively with an increased risk of a type of liver cancer, according to a new study in the February 16 issue of the Journal of the National Cancer Institute.
Chronic infection with HBV has been established as a cause of hepatocellular carcinoma (HCC), a type of liver cancer. More than 350 million people worldwide have a chronic infection with one of the seven known genotypes, or subtypes, of HBV. Although there are some known risk factors for HCC development, it is unclear what role HBV subtype or viral load--the amount of the virus in the blood--might have on cancer development.
To determine whether HBV genotype and viral load are associated with HCC risk, Ming-Whei Yu, Ph.D., of National Taiwan University in Taipei, and colleagues conducted a nested case–control study among male Taiwanese HBV carriers who had not been diagnosed with HCC. HBV DNA levels--a measure of viral load--and genotypes were determined for 154 case patients (men who were diagnosed with HCC during 14 years of follow-up) and 316 control subjects.