Oncogenes, the abnormal forms of proto-oncogenes, were shown to be involved in malignant transformation and in tumor progression. c-erbB2/HER2/neu is member of EGFR family and encodes the p185 protein, which functions as a tyrosine-kinase. Gene amplification and/or p185 overexpression were reported to be associated with poor prognostic in cancer. Our purpose was to investigate p185 immunohistochemical expression in breast carcinomas and in the corresponding axillary lymph nodes metastases and to identify possible correlation between p185 and other factors of poor prognostic, such as loss of hormonal receptors expression. In our study, 40.91% of cases were erbB-2 positive, p185 expression being maintained from the primary tumors to axillary metastases and associated with positive nodal status and with the absence of hormonal receptors expression (p < 0.05). These findings support the hypothesis the c-erbB2 is an advantageous acquisition for the aggressive behavior of the tumor cell and for its ability to invade and metastasize.