Relationships between epidermal growth factor receptor (EGF-R) and other predictors of prognosis in breast carcinomas. An immunohistochemical study

The importance of epidermal growth factor receptor (EGF-R) as an immunohistochemical factor of prognosis has been investigated in 820 cases of breast carcinoma irrespective of subtyping. An immunohistochemical membrane positivity for EGF-R (Ab1, clone 455 and Ab2, clone 528, Oncogene Science Manhasset NY, USA, ABC-peroxidase method) has been observed in neoplastic cells of 131/820 breast carcinomas (15.9%); the percentage is lower than those of the majority of reported series, but the total number of cases is higher. A significant inverse relationship between EGF-R and estrogen/progesterone receptors has been found (ER-ICA, PgR-ICA, Abbott, PAP-method). Highly proliferating Ki67 positive (> = 20% stained nuclei-Dakopatts Denmark) and oncoprotein p53 (Pab 1801 clone, Oncogene Science) positive carcinomas are more frequently EGF-R positive (p < 0.001). No relationship exists between EGF-R expression, c-erbB-2 (3B5 clone, Oncogene Science) expression, tumor size and lymph node status. The detection of EGF-R may be a useful addition to other immunohistochemical prognosticators, but it must be related with clinical outcome in further studies.