Inclusion Criteria:

- Histological or cytological diagnosis of breast cancer

- Stage IV disease

- None or at most one prior treatment for metastatic disease (prior treatment with
trastuzumab for metastatic disease is not permitted)

- Overexpression of HER-2 (immunohistochemistry 3+) or genetic amplification of
c-erbB2/neu (FISH+)

- ECOG Performance Status 0-2

- Age >18 and < 75 years

- Left Ventricular Ejection Fraction (LVEF) >50%

- Life expectancy >3 months

- Signed informed consent

Exclusion Criteria:

- Absence of measurable or evaluable disease

- Life expectancy < 3 months

- ECOG performance status > 2

- History of prior malignancy in the last 5 years (other than adequately treated
non-melanoma skin cancer or excised cervical carcinoma in situ).

- Previous chemotherapy with vinorelbine or carboplatin (as adjuvant therapy or for
metastatic disease)

- Previous therapy with trastuzumab for metastatic disease (previous adjuvant therapy
with trastuzumab is permitted)

- Neutrophil < 2000/mm3, platelets < 100,000/mm3, haemoglobin < 9 g/dl

- Creatinine > 1.5 x the upper normal limits

- GOT and/or GPT > 2.5 x the upper normal limits and/or Bilirubin > 1.5 x the upper
normal limits in absence of hepatic metastases

- GOT and/or GPT > 5 x the upper normal limits and/or Bilirubin > 3 x the upper
normal limits in presence of hepatic metastases

- Congestive hearth failure or history of congestive heart failure, unstable angina
pectoris even if it is medically controlled, myocardial infarction, clinically
significant valve disease, uncontrolled arrhythmia

- Any concomitant pathology that would, in the investigator's opinion, contraindicate
the use of the drugs in this study

- Male gender

- Pregnant or lactating women

- Refusal or incapacity to provide informed consent

- Inability to comply with follow up