Inclusion Criteria:

- age≥18y

- KPS≥ 70

- pathologic diagnosis of breast cancer

- at least 1 measurable lesion as defined by modified RECIST criteria

- screening laboratory values with the following parameters: hemoglobin:≥10.0 g/dl
absolute neutrophils count:≥1.5×109/L platelet:≥100×109/L creatinine clearance rate:
≥60ml/min total bilirubin: ≤1.5 ×upper limits of normal Alkaline
phosphatase,Aspartate aminotransferase and Alanine aminotransferase:≤ 2.5×upper
limits of normal（≤5×upper limits of normal if liver metastasis are present)

- signed ICF

- for women of child bearing potential,a negative serum or urine pregnancy test result
before study entry.

Exclusion Criteria:

- More than 2 cytotoxic chemotherapy treatment regimens for metastatic disease.

- prior exposure to 5-Fluorouracil continuous infusion.

- prior exposure docetaxol for metastatic disease

- Any other cancer within 5 years prior to screening with the exception of
contralateral breast cancer,adequately treated cervical carcinoma in situ,or
adequately treated basal or squamous cell carcinoma of skin