1. Patients with histologic confirmation of metastatic (stage IV) 'triple receptor-negative' breast cancer. Tissue must be available at baseline or agree to biopsy. The diagnosis of 'triple receptor-negative' breast cancer requires that either the primary tumor or a metastatic deposit be shown to be negative for estrogen receptors (ER) and progesterone receptors (PR) by immunohistochemistry (IHC) and for HER2/neu by IHC (i.e. a score of 0 and 1+) or fluorescent in situ hybridization (FISH).