Analyses of proliferating cell nuclear antigen-positive cells in hepatocellular carcinoma: comparisons with clinical findings.

Proliferating tumour cells in 92 patients with hepatocellular carcinoma (HCC) were identified by an immunohistochemical method using a monoclonal antibody against proliferating cell nuclear antigen (PCNA). The rate of PCNA-positive cells in HCC tissues was positively correlated with histological grade and the tumour size and T factor of the tumour. In order to analyse the relationship between prognostic factors and cumulative survival rate after obtaining tumour specimens, 49 patients whose clinical courses could be followed after needle biopsy were selected for evaluation. These patients were treated by medical therapy alone. Analyses of prognostic factors by Cox's proportional hazard model revealed that the patient's prognosis was significantly correlated with PCNA-positive rates as well as the tumour size and mode of therapy. Moreover, the cumulative survival rates were significantly (P < 0.001) higher in patients with rates of PCNA-positive cells < 15% than in those with > or = 15%, even when tumour sizes were under 50 mm or tumours demonstrated the same degree of histological differentiation. These findings indicate that the PCNA-positive rate in biopsied tissues provides useful prognostic information in patients with HCC treated only by medical therapy.