C-erb-B-2 oncoprotein and epidermal growth factor receptor in human hepatocellular carcinoma: an immunohistochemical study.

The aim of this study was to evaluate the immunohistochemical expression of epidermal growth factor (EGFR) and c-erb-B-2 oncoprotein in a series of 71 hepatocellular carcinomas as well as in the adjacent hepatic tissue and to assess any correlation with HBsAg expression. The total of the 71 hepatocellular carcinomas (HCCs) was classified into 17 low grade and 54 high grade cases with adjacent non-neoplastic liver parenchyma, observed in 14 and 28 cases respectively. Coexisting cirrhosis or fibrosis was noticed in the adjacent non-neoplastic parenchyma in 12 cases of low grade and 22 cases of high grade HCC. The immunohistochemical avidin-biotin-peroxidase complex (ABC) method was performed on formalin-fixed paraffin sections for the detection of EGFR, c-erb-B-2 oncoprotein and HBsAg using monoclonal antibodies. The expression of c-erb-B-2 was observed in 29.5% (21/71) of the HCCs showing no statistically significant correlation with histological grade. The c-erb-B-2 was also detected in the adjacent non-neoplastic parenchyma in 7/14 low grade HCCs, and in 9/28 high grade HCCs. No statistically significant differences in c-erb-B-2 oncoprotein expression were observed between the HCCs and the adjacent non-neoplastic parenchyma. In addition, HBsAg was detected in 10/42 examined cases of HCC with adjacent non-neoplastic parenchyma, while only 4 cases of HCCs were simultaneously positive for c-erb-B-2 and HBsAg. EGFR was detected in only 3/71 cases of HCC, while the antigen was not detected at all in the adjacent non neoplastic parenchyma. HBsAg expression was not observed in any of the EGFR-positive HCCs. Our results suggest that both c-erb-B-2-oncoprotein and EGFR do not seem to be predominantly involved in the transformation of hepatocytes to the malignant phenotype.