Statement: Patients of any ethnicity can participate in the primary trial.
Primary_evidence: Inclusion Criteria:   Female patients with histologically or cytologically confirmed carcinoma of the breast   Patients with advanced/metastatic disease that is not amenable to curative therapy (either surgery or radiation therapy)   Patients must have measurable disease by the RECIST criteria, defined as at least one lesion that can be accurately measured in at least one diameter (at least 10 mm in longest diameter (LD) by spiral computer tomography (CT) scan, or at least 20 mm by standard techniques; If the only measurable lesion is a lymph node, it must measure at least 20 mm in LD. If a single lesion is identified as the target lesion, a cytological or histological confirmation of breast carcinoma is required.   Patients must have had prior treatment with an anthracycline and a taxane (either sequential or in combination) and may have had prior treatment with other agents as well.   Patients must have progressed within six months of the last dose of chemotherapy, or experienced disease progression while receiving chemotherapy for advanced/metastatic disease.   Resolution of all chemotherapy or radiation-related toxicities to less than grade 1 severity   Age  18 years   Eastern Cooperative Oncology Group (ECOG) Performance Status (APPENDIX 4) of 0 or 1   Life expectancy of  3 months   Adequate renal function as evidenced by serum creatinine  1.5 mg/dL or calculated creatinine clearance  50 mL/minute (min) per the Cockcroft and Gault formula   Adequate bone marrow function as evidenced by absolute neutrophil count (ANC)  1.5 x 10^9/L, hemoglobin  10.0 g/dL (a hemoglobin <10.0 g/dL would be acceptable if it can be corrected by growth factor or transfusion), and platelet count  100 x 10^9/L   Adequate liver function as evidenced by bilirubin  1.5 mg/dL and alkaline phosphatase, alanine transaminase (ALT), and aspartate transaminase (AST)  3 times the upper limits of normal (ULN) (in the case of liver metastases  5 x ULN)   Patients willing and able to complete the FACT-B questionnaire, Analgesic Diary, Pain VAS, and the tumor-related symptomatic assessment   Patients willing and able to comply with the study protocol for the duration of the study   A sample from the diagnostic biopsy (paraffin block) must be available   Written informed consent prior to any study-specific screening procedures with the understanding that the patient may withdraw consent at any time without prejudice Exclusion Criteria:   Patients who have received chemotherapy, radiation, hormonal therapy, or Herceptin within 2 weeks of E7389 treatment start   Radiation therapy encompassing > 10% of marrow   Failure to recover from any chemotherapy related or other therapy related toxicity at study entry that is deemed to be clinically significant by the study investigator   Prior treatment with Mitomycin C or nitrosoureas   Prior high dose chemotherapy with hematopoietic stem cell rescue in the past two years   Pulmonary lymphangitic involvement that results in pulmonary dysfunction requiring active treatment, including the use of oxygen   Active symptomatic brain metastasis; Patients with central Nervous System (CNS) metastasis are considered eligible if they have completed local therapy and discontinued from corticosteroids for at least two weeks before starting treatment with E7389   Patients with meningeal carcinomatosis   Patients who require therapeutic anti-coagulant therapy with Warfarin or related compounds; Mini dose warfarin for catheter related thrombosis prophylaxis is permitted   Women who are pregnant or breast-feeding; Women of childbearing potential with either a positive pregnancy test at Screening or no pregnancy test. Women of childbearing potential unless (1) surgically sterile or (2) using adequate measures of contraception in the opinion of the Investigator. Postmenopausal women must be amenorrheic for at least 12 months to be considered of non-childbearing potential.   Severe /uncontrolled intercurrent illness/infection   Significant cardiovascular impairment (history of congestive heart failure > NYHA grade II, unstable angina or myocardial infarction within the past six months, or serious cardiac arrhythmia)   Patients with organ allografts   Patients with known positive HIV status   Patients who have had a prior malignancy, other than carcinoma in situ of the cervix, or non-melanoma skin cancer, unless the prior malignancy was diagnosed and definitively treated  5 years previously with no subsequent evidence of recurrence   Patients with pre-existing neuropathy > Grade 1   Patients with a hypersensitivity to halichondrin B and/or halichondrin B chemical derivative   Patients who participated in a prior E7389 clinical trial   Patients with other significant disease or disorders that, in the Investigator's opinion, would exclude the patient from the study