Inclusion Criteria:

• Written informed consent.
• Women older than 18 years old.
• HER2 positive breast cancer with histological diagnoses.
• Non-operable locally advanced or metastatic disease, previously treated with trastuzumab and taxanes.
• Measurable or non-measurable disease as per Response Evaluation Criteria in Solid Tumors (RECIST).
• Disease progression during or after treatment with trastuzumab and taxanes.
• Maximum of 1 previous chemotherapy line for advanced or metastatic disease.
• Previous radiotherapy is allowed if radiated area is not the only documented lesion.
• At least 4 weeks since the last administration of antineoplastic treatment and all toxicities resolved.
• Performance status Eastern Cooperative Oncology Group (ECOG) >=2.
• Life expectancy of at least 12 weeks.
• Left Ventricular Ejection Fraction (LVEF) evaluation (>=50%) in previous 4 weeks.

• Hematology:

  • neutrophils >=1.5 x 10e9/l;
  • platelets >= 100 x 10e9/l;
  • hemoglobin >= 10 mg/dl

• Hepatic function:

  • total bilirubin <= 1.5 xUNL;
  • SGOT and SGPT and alkaline phosphatase <= 2.5xUNL, or <=5xUNL if hepatic lesions present

• Renal function:

  • creatinine <= 175 µmol/l (2 mg/dl);
  • creatinine clearance >= 60 ml/min.
• Patients able to comply with treatment and follow-up.
• Negative pregnancy test in the previous 14 days. Adequate contraceptive method during treatment and up to 3 months after finalised.
• Brain metastatic lesions are allowed provided all other criteria are met.
• Male who met inclusion criteria are eligible.

Exclusion Criteria:

• History of hypersensitivity to vinorelbine, trastuzumab, rat proteins or trastuzumab components.
• History of dyspnea at rest, or chronic oxygen therapy required.
• Active infection.
• Second malignancy, except for cervical in situ carcinoma, basal skin carcinoma, adequately treated. Previous malignancies with a 5 year disease free survival are allowed.
• Pregnant or lactating women.
• Any other serious medical pathology, such as congestive heart failure, unstable angina, history of myocardial infarction during the previous year, uncontrolled HA or high risk arrhythmias.
• History of neurological or psychiatric disorders, which could preclude the patients to free informed consent.
• Active uncontrolled infection.
• Active peptic ulcer, unstable diabetes mellitus.
• Concomitant treatment with other investigational products. Participation in other clinical trials with a non-marketed drug in the 30 previous days before randomization.
• Concomitant treatment with other therapy for cancer.