Practice guidelines from the American Association
for the Study of Liver Diseases recommend surveillance
for patients at high risk for hepatocellular
carcinoma.26 Collectively, the strength of the
evidence supporting the efficacy of surveillance in
high-risk groups is modest. One randomized, controlled
trial of nearly 19,000 HBV-infected patients
in China showed that surveillance consisting of
measurement of serum alpha-fetoprotein levels and
ultrasonographic imaging every 6 months was
associated with a 37% reduction in mortality related
to hepatocellular carcinoma.27 However, another
randomized, controlled trial involving HBVpositive
patients in China showed that surveillance
was not beneficial.28 There are no data from randomized
trials of surveillance in patients with HCV
or in patients with cirrhosis. Several nonrandomized
trials and observational studies have shown
a survival benefit in patients with small hepatocellular
tumors, but these studies had unavoidable
biases.29,30