The status of the axillary lymph nodes (AX) is widely accepted as the most significant prognostic factor in breast cancer. Nevertheless, there are large differences in the clinical outcomes of patients with the same AX status, which suggest that we should seek further prognostic variables. At present, several biologic factors, such as DNA ploidy, c-erbB-2 expression, EGFR, p53 alteration, and HPA staining, have been proposed. However, their value as prognostic indicators remains undetermined. Whether these factors are independent prognostic factors, or merely related to other variables, such as AX metastasis, is unclear. A clear need for a new biologic markers to serve as more reliable prognostic factors exists.