Survivin is a novel inhibitor of apoptosis. It is detected in fetal and neoplastic adult tissue, but not in normal tissues. Several recent studies have shown that survivin not only inhibits apoptosis, but also accelerates cancer cell proliferative activity. Expression of the protein may be of prognostic significance and therapeutic relevance in many cancers. We investigated survivin expression in hepatocellular carcinoma, correlating results with proliferation (MIB-1), prognostic factors, and outcome. Paraffin-embedded sections of 72 hepatocellular carcinoma were immunostained for survivin and MIB-1 using tissue microarray technology. Expression was evaluated in nuclei and cytoplasm as intensity (0-3+), and percentage of positive cells scored on a four-tiered system with less than 10%=negative; 10-25%=1; 26-50%=2; 51-75%=3; and 76-100%=4. Frequency of nuclear survivin expression was 43%. There was a significant correlation between nuclear survivin expression and nuclear grade (P=0.0271), microvascular invasion (P=0.0064), mitotic rate (P=0.0017), and MIB-1 (P=0.0001), as well as local recurrence (P=0.0487), and disease-free survival (P=0.0098). Histologic grade (P=0.0544) and stage (P=0.0548) tended to correlate with survivin expression, which did not correlate with cirrhosis, tumor necrosis, multiple tumors, metastatic disease, or overall survival. Survivin expression correlates with poor prognostic parameters (high nuclear and histologic grade, microvascular invasion, increased proliferation (mitotic count, MIB-1)), local recurrence, and shorter disease-free survival, but does not correlate with overall survival. An important role is suggested for survivin in progression, recurrence, and treatment of hepatocellular carcinoma.