Inclusion Criteria:

- Adult male or female patients, >/= 18 years of age

- Histologically confirmed early invasive HER2-positive carcinoma of the breast with no
evidence of residual, locally recurrent or metastatic disease and defined as clinical
stage I to IIIC that is eligible for adjuvant treatment with trastuzumab

- Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1

- Screening left ventricular ejection fraction (LVEF) >/= 55%

Exclusion Criteria:

- Previous neoadjuvant or adjuvant breast cancer treatment with an approved or
investigational anti-HER2 agent

- History of other malignancy, except for curatively treated carcinoma in situ of the
cervix or basal cell carcinoma and patients with other curatively treated
malignancies, other than breast cancer, who have been disease-free for at least 5
years

- Past history of ductal carcinoma in situ that has been treated with any systemic
therapy or with radiation therapy to the ipsilateral breast where the invasive cancer
subsequently develops

- Metastatic disease

- Inadequate bone marrow, hepatic or renal function

- Serious cardiac or cardiovascular disease

- Uncontrolled hypertension, or history of hypertensive crisis or hypertensive
encephalopathy

- History of severe allergic or immunological reactions, e.g. difficult to control
asthma

- Pregnant or lactating women