Treatment of Brain Metastases From Breast Cancer With Eribulin Mesylate

Primary Objectives: To determine the 3-month central nervous system (CNS)-progression free survival (PFS) for patients with metastatic breast cancer with brain metastases treated with eribulin mesylate. Secondary Objective(s): 1\. Estimate CNS complete and partial response rates (CR and PR) and duration of CNS response in this patient population. 2 Evaluate toxicity in patients with breast cancer with brain metastases treated with eribulin mesylate. 3 Estimate clinical benefit rate (CBR) at 3 months in breast cancer patients with brain metastases treated with eribulin mesylate. (CBR is the sum of CR, PR and stable disease at 3 months). 4 To estimate systemic disease (extra cranial) response rate and duration of systemic response in this patient population. 5 Overall survival in this patient population. Design: This is a phase II study that will require patients to evaluate the primary objective (CNS PFS at 3 months). Study patients will have a baseline brain MRI and a second MRI at 12 weeks to evaluate disease.