Significance of epidermal growth factor receptor expression in breast cancer.

Recent interest of many investigators is focused on epidermal growth factor receptor (EGFR) family, because of their potential role in the pathogenesis and progression of breast cancer. Paraffin tumor sections were collected retrospectively from 181 breast cancer patients diagnosed between 2002 and 2003. Immunohistochemical staining with ErbB-1, ErbB-2, ErbB-3, and ErbB-4 monoclonal antibodies was performed. The ErbB expression was correlated with the other clinicopathological variables. Overexpression of ErbB-1, ErbB-2, ErbB-3, and ErbB-4 was observed in 20.6, 18.2, 14.3, and 5.7% cases, respectively. Overexpression of ErbB-1 and ErbB-2 was associated with poor prognostic features and decreased 5-year disease-free survival. The patients with co-overexpression of ErbB-1 and ErbB-2 had a shorter DFS, although this difference was not statistically significant. ErbB-1 overexpression may indicate a subset of patients with a poor disease prognosis. Assays for ErbB-1 and ErbB-2 may be more useful than a single assay in predicting prognosis of a breast cancer patient.