Does antiviral therapy for hepatitis B and C prevent hepatocellular carcinoma?

Approximately 75% to 80% of hepatocellular carcinomas (HCC) worldwide are attributed to chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infection. Thus, effective prevention of HBV and HCV infection and progression from acute HBV and HCV infection to chronic hepatitis, cirrhosis and HCC might prevent as many as 450,000 deaths from HCC each year. The most effective approach to preventing HCC is to prevent HBV and HCV infection through vaccination. Indeed HBV vaccine is the first vaccine demonstrated to prevent cancers. However, a vaccine for HCV is not available and for persons who are chronically infected with HBV or HCV, antiviral therapy is the only option for preventing HCC. Direct evidence supporting a benefit of antiviral therapy on the prevention of HCC has been shown in a few randomized controlled trials. There is abundant evidence that antiviral therapy, in patients with long-term virological response, can improve liver histology, providing indirect support that antiviral therapy may prevent HCC by slowing progression of liver disease and possibly even reversing liver damage. Nevertheless, the risk of HCC remains in patients with chronic HBV or chronic HCV infection if treatment is initiated after cirrhosis is established. These data indicate that treatment might be of greater benefit if instituted earlier in the course of chronic hepatitis B or C. Safer, more effective, and more affordable antiviral therapies are needed for both hepatitis B and hepatitis C so more patients can benefit from treatment and more HCCs can be prevented.