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.

Inclusion Criteria:

• Clinical status of lymph nodes must be available
• Sonographical status of lymph nodes must be available
• Patients must consent to documentation of cancer treatment
• Histologic diagnosis of invasive breast cancer, clinical stage T1-4, M0 (non-inflammatory T4c)
• Patients scheduled for neoadjuvant chemotherapy
• Treatment with a 3-weekly FEC or AC regimen (3-4 cycles) followed by 3-4 cycles of q3 weekly docetaxel or paclitaxel.
• Local HER2 status of tumor biopsy must be negative.

Exclusion Criteria:

• The patient has a prior history of invasive or metastatic breast cancer.
• The patient had prior excisional biopsy of the primary invasive breast cancer.
• The patient had prior ipsilateral sentinel axillary lymph node biopsy for breast cancer.
• The patient cannot safely or feasibly undergo biopsy of the primary tumor.
• The patient has a diagnosis of Stage IV (distant metastatic) breast cancer.
• The patient has proven HER2-positive breast cancer, defined as a pathology report of amplification of the gene or 3+ score for immunohistochemical staining.

Breast cancer patients with advanced HER 2 negative breast cancer