Inclusion Criteria:

- Histologically/cytologically confirmed breast cancer

- Metastatic breast cancer, having at least one target lesion according to the RECIST
criteria. Bone metastases, leptomeningeal disease, ascites, pleural or pericardial
effusions, inflammatory breast disease, lymphangitic spread or cystic lesions are not
acceptable as target lesions. Target lesions must be ≥ 10 mm longest diameter
measured in one dimension using spiral CT, or ≥ 20 mm longest diameter measured in
one dimension using conventional techniques. In addition to the definitions
pertaining to the target lesion(s) from the RECIST criteria above, the target
lesion(s) must not have been previously irradiated (newly arising lesions in
previously irradiated areas are acceptable).

- Age > 18 years

- Signed informed consent obtained prior to initiation of any study-specific procedures
or treatment

Exclusion Criteria:

- Prior cytotoxic chemotherapy or active/passive immunotherapy for metastatic breast
disease

- Prior usage of capecitabine or mitomycin as adjuvant or neoadjuvant treatment

- Life expectancy < 3 months

- Not-ambulatory or with an ECOG performance status > 1

- Insufficient hematological, renal and hepatic functions:

- hemoglobin < 8.0 g/dL

- absolute neutrophils count (ANC) < 1.5 x 109/L

- platelet count < 100 x 109/L

- serum creatinine > 1.25 x N*

- total bilirubin > 2.0 x N*

- ASAT and/or ALAT > 2.5 x N* (in case of liver metastases > 5 x N*)

- alkaline phosphatase > 2.5 x N* (in case of liver metastases > 5 x N*, in case of
bone metastases > 10 x N*) *N = upper limit of standard range

- Severe renal impairment [creatinine clearance < 30 mL/min (calculated according to
cockcroft and Gault)]