Abstract: Objective To investigate patterns of CD34 expression and microvessel density（MVD） in hepatocellular carcinoma （HCC），focal nodular hyperplasia（FNH） and hepatic adenoma（HA）. Methods Samples from patients with HCC （n=32），FNH （n=12）and HA（n=5）were analyzed by immunohistochemistry using an anti-CD34 antibody.MVD was also measured in all samples. Results CD34 was expressed in all three types of hypervascular hepatic mass.The MVD was significantly lower in HCC than in the benign lessions FNH and HA（P<0.05）. Conclusions The significantly lower MVD in HCC compared to FNH and HA may allow imaging-based diagnosis of the disease.

Key words: Hepatocellular neoplasms, Hepatocellular carcinoma, Focal nodular hyperplasia, Hepatic adenoma, CD34, Microvessel density