Abstract: | An immunohistochemical study of the c-erbB-2 protein was conducted on formalin-fixed paraffin-embedded tissue sections from 136 primary gastric carcinomas and 50 metastatic lymph node tumors obtained at gastrectomy. Expression of the protein was detected in 35 of 136 primary gastric carcinomas (25.7%) and 22 of 50 metastatic lymph nodes (44%). The staining pattern of tumor cells was classified as membranous or cytoplasmic. An immunohistochemical study using serially diluted antibody demonstrated that 82.6% of positive cases in metastatic lymph nodes showed c-erbB-2 immunoreactivity stronger than that in the primary tumors. Membranous staining was stronger than cytoplasmic staining. c-erbB-2 protein of the cytoplasmic as well as membranous types was confirmed to be a 185-kDa whole molecule by immunoblotting. Correlation between the expression of c-erbB-2 protein and clinical and histological parameters was investigated. No significant correlation between 5-year survival rate of patients and expression of c-erbB-2 protein was found. In the poorly differentiated carcinoma group possessing c-erbB-2 protein, overall survival was significantly shorter than in cases without protein expression ( p < 0.01). We conclude that c-erbB-2 protein is not a useful prognostic indicator in gastric carcinomas. |