A genomic test was developed to predict chemo-sensitivity to taxane-anthracycline-based chemotherapy as neoadjuvant treatment. The primary aim of this study is to prospectively evaluate the microarray-based, genomic test as a predictor of axillary lymph node response. Also, to determine whether the probability of achieving negative axillary nodes, is sufficiently high for patients whose breast cancer is predicted to be chemo-sensitive to support omitting axillary dissection.