Prognostic factors known in breast cancer are lymph node involvement, tumor size, distant metastasis status, tumor cellular differentiation degree, patient’s age, state of hormone receptors in tumor, HER2 overexpression, tumor proliferation index, lymphovascular invasion, tumor histology, response to neoadjuvant chemotherapy and hormonotherapy and p53 mutation. This evidence concerns the gene ERBB2 and breast carcinoma.