Prognostic and predictive value of epidermal growth factor receptor in recurrent breast cancer.

PURPOSE The prognostic and predictive value of epidermal growth factor receptor (EGFR) expression was evaluated in patients with recurrent breast cancer. EXPERIMENTAL DESIGN The immunohistochemical expression of EGFR was analyzed in 241 patients with recurrent breast cancer. RESULTS EGFR expression was positive in 87 of 241 (36%) patients with recurrent breast cancer, whereas the EGFR expression inversely correlated with the estrogen receptor (ER) status. The patients with positive EGFR expression had a significantly worse postrelapse survival than those with a negative EGFR expression, whereas EGFR expression also had a postrelapse prognostic significance in patients with a positive ER status. A multivariate analysis indicated EGFR expression to be an independently significant factor for postrelapse survival, whereas a multivariate analysis in which the ER status was added to variables indicated that ER status but not EGFR expression to be an independently significant factor. There was a significant difference between positive and negative EGFR expression in the treatment response of 82 patients who received hormonal therapies and 374 patients who received chemotherapies, whereas a multivariate analysis indicated the responses to the first-line treatment and EGFR expression to be independently significant factors for postrelapse survival. CONCLUSIONS EGFR expression had prognostic significance in recurrent breast cancer, whereas its prognostic value was not independent of the ER status. In addition, the EGFR expression was suggested to be related to the responses to hormonal therapy and chemotherapy, whereas the EGFR expression had an additional prognostic value that was independent of the treatment response.