能否预防慢性乙肝转变为肝癌？

Henry L.Y. Chan*. Department of Medicine and Therapeutics,The Chinese University of Hong Kong

Hepatitis B virus (HBV) infection is the commonest cause of hepatocellular carcinoma (HCC) most countries in Asia. After the launching of the universal vaccination program, the incidence of childhood HCC has been dramatically reduced in Taiwan. As HCC in adult commonly develop at the age the 40 to 50 years, it may take another 20 to 30 years before one can see a significant reduction in incidence of adult HCC.

Clearance of HBsAg is the marker of ultimate viral control in chronic hepatitis B. If HBsAg clearance occurs before the age of 50, the prognosis is excellent. However, spontaneous HBsAg clearance is rare. Peginterferon and oral antiviral agents can induce HBsAg clearance in about 10% and 5% of patients, respectively. High HBV DNA has been found to associate with higher risk of HCC. However the data from individual studies on the long term benefit of interferon or antiviral agent is conflicting.

A meta-analysis has been conducted to investigate the beneficial effect of interferon and antiviral agents (mainly lamivudine) on HCC. Interferon is associated with an approximate 33% reduction in risk of HCC. Lamivudine is associated with an approximate 80% reduction in risk of HCC.

In summary, vaccination can prevent HCC by preventing HBV infection. HBsAg clearance in an early age can almost prevent HCC. Interferon and antiviral treatment can reduce the risk but not completely prevent HCC.