Hepatitis C virus genotype 1b increases cumulative lifetime risk of hepatocellular carcinoma.

The association between subtypes of hepatitis C virus (HCV) and risk of hepatocellular carcinoma (HCC) remained inconclusive and evaluated in both case-control and cohort studies. In the case-control study, 397 HCC cases from medical centers were compared with 410 community-based non-HCC controls. All of them were anti-HCV-seropositive, HBsAg-seronegative with serum HCV RNA levels ≥1,000 IU/mL. Logistic regression models were used to estimate the odds ratio (OR) with 95% confidence interval (95% CI) of HCV subtype after controlling for other HCC risk factors. In the cohort study, 866 anti-HCV-seropositive individuals were followed from 1991 to 2008 to assess the long-term HCC predictability of HCV subtypes. Newly developed HCC cases were ascertained by follow-up health examinations and computerized linkage with national databases. The percentage of HCV 1b subtype was higher among HCC cases than controls (64 vs. 55%, p < 0.001). Participant infected with HCV 1b had a higher mean serum HCV RNA level (2.0 × 10(6) IU/mL) than those infected with HCV non-1b (1.2 × 10(6) IU/mL, p < 0.001). The multivariate-adjusted OR (95% CI) of developing HCC for HCV 1b comparing to non-1b was 1.43 (1.02-2.02). After the long-term follow-up, the cumulative lifetime (30-80 years old) HCC risk was 19.2 and 29.7% for patients infected with HCV non-1b and 1b, respectively (p < 0.001). The multivariate-adjusted hazard ratio (95% CI) was 1.85 (1.06-3.22) for HCV 1b compared to non-1b. HCV subtype 1b, the most prevalent subtype in Taiwan, was associated with an increased HCC risk and a proactive clinical management is suggested for patients with HCV 1b.