- No prior therapies (except for anti-estrogen therapy) are allowed for the treatment of the newly diagnosed metastatic breast cancer; patients are allowed to have had prior chemotherapy for breast cancer in the adjuvant setting for at least 12 months prior to enrollment into this study; patients with a prior diagnosis of malignancy treated >= 5 years ago are eligible, provided that they have not received prior nab-paclitaxel as part of their prior treatment regimen, and that they meet all eligibility criteria