female 18 years or older

histologically confirmed, completely excised invasive breast cancer with her-2 overexpression

primary surgery less than twelve weeks prior to registration

lvef>50% as assessed by transthoracic echocardiogram or gated heart pool scan

eastern cooperative oncology group performance status 0-2

adjuvant systemic treatment plan comprises at least three cycles of anthracycline chemotherapy and 52 weeks of trastuzumab

before patient registration, informed consent must be given according to local regulations.

pregnancy

distant metastases from breast cancer

any systemic chemotherapy prior to study entry