Clinicopathologic features and prognosis of resected hepatocellular carcinomas of varied sizes with special reference to proliferating cell nuclear antigen

Abstract

Proliferating cell nuclear antigen (PCNA) is an intranuclear protein that is linked closely to the cell cycle. An immunohistochemical study was performed on the expression of PCNA in various sized hepatocellular carcinomas (HCCs) to determine the relation between the proliferative activity of cancer cells and prognosis. One hundred forty-one neoplasms resected from 141 patients who underwent hepatic surgery for HCC at Kyushu University hospital from April, 1991, to July, 1993, were studied immunohistochemically using monoclonal antibody for PCNA (PC10), and analyzed for a possible correlation between PCNA labeling index (PCNA-LI) and the prognosis of patients with HCC. Proliferating cell nuclear antigen reactive cancer cells were observed throughout the HCC. The PCNA-LI ranged from 1.2%-91.6%, with a mean of 37.7%. The high PCNA-LI (> 37.7) group showed a significantly higher incidence of tumor thrombus in the portal vein, higher Edmondson's Grade, and a higher recurrence rate than the low PCNA-LI (< 37.7) group. Hepatocellular Carcinomas were divided into three groups according to tumor size. Based on the clinicopathologic findings, in small (< 30 mm) HCCs, the high PCNA-LI (> 29.0) group showed a significant higher Edmondson's grade and a higher recurrence rate than the low PCNA-LI (< 29.0) group. In medium (30-60 mm) HCCs, the high PCNA-LI (> 36.1) group showed a significantly higher recurrence rate than the low PCNA-LI (< 36.1) group, although there was no difference in the pathologic findings between the high (> 59.4) and low (< 59.4) PCNA-LI groups. Proliferating cell nuclear antigen labeling index is closely related to cell differentiation and the prognosis of HCC. Furthermore, PCNA-LI was found to be useful in predicting the intrahepatic spread and prognosis of small (< 30 mm) and medium (30-60 mm) but not large (> 60 mm) HCCs.