['As most cases of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) have concurrent cirrhosis, viral factors identified to be associated with HCC might be related to cirrhosis rather than HCC.', 'Hepatitis B virus DNA levels, genotypes and precore/basal core promoter (BCP) mutants were compared between cirrhotic HCC and non-cirrhotic HCC patients. Age- and sex-matched case-control studies were performed to identify the risk factors.', 'Hepatitis B virus DNA levels showed no significant difference between non-cirrhotic HCC patients (n=20) and cirrhotic HCC patients (n=140) or 1 : 3 age- and sex-matched cirrhotic HCC patients (n=60), but genotype C and BCP mutant were significantly more prevalent in the latter than in the former. In multiple logistic regression, BCP mutant but not genotype C correlated significantly with the presence of cirrhosis in HCC patients. Compared with inactive carriers (n=60), non-cirrhotic HCC patients (n=20) had significantly higher HBV DNA levels but no difference in HBV genotypes and precore/BCP mutants. Furthermore, HBV DNA levels, the distribution of HBV genotypes and the prevalence of precore/BCP mutants all failed to show any significant difference between cirrhotic HCC patients (n=60) and cirrhotic patients without HCC (n=60).'] Is basal core promoter mutation associated with progression to cirrhosis rather than hepatocellular carcinoma in chronic hepatitis B virus infection?