The present clinical trial will investigate the safety and efficacy of a sequential preoperative therapy with Epirubicin/Cyclophosphamide in combination with Paclitaxel/Trastuzumab, followed by postoperative Trastuzumab in patients with HER-2 overexpression primary breast cancer.

Inclusion Criteria:

1. Primary carcinoma of the breast, confirmed histologically by core biopsy (at least 3 core biopsy samples)
2. Tumor lesion of the breast with a palpable or a imagistic size ≥ 2 cm or inflammatory breast cancer
3. Known HER-2 status detected on core biopsy. HER-2 over expression is defined as DAKO HercepTest (3+) or DAKO HercepTest (2+) and FISH (+) (fluorescence-in-situ-hybridisation).
4. No distant metastatic disease, confirmed by chest x-ray, abdominal sonography and bone scan.
5. Female patients
6. Age ≥ 18 and ≤ 65 years
7. ECOG < 2/WHO 0-1
8. Laboratory requirements GOT and Bilirubin < 1.5x UNL Leukocytes >= 3 G/l Neutrophile > 1 G/l Thrombocytes > 100 G/l Creatinine (Serum) < 2.0 mg/dl.
9. Normal cardiac function, confirmed by cardiologist
10. No active hepatitis
11. Written informed consent for all study procedures
12. Patients must be available and compliant for treatment and follow-up

Exclusion Criteria:

1. Multicentricity in various quadrants (contact the study office)
2. CNS-metastases
3. Secondary malignancy, excluding basalioma of the skin or carcinoma in situ of the cervix that has received curative therapy
4. Patients with relevant hemodynamic cardial diseases
5. Patients with a left ventricular ejection fraction (LVEF) under the normal limit of the institution, confirmed by echocardiography or MUGA-Scan.
6. Uncontrolled, severe comorbidities
7. Patients with severe respiratory diseases and severe dyspnea and / or which need supportive oxygen
8. Previous anti-HER2-therapy
9. Patients receiving immunosuppressant therapy
10. Known allergy to medication containing cremophor
11. Hb <10 g/dL, Neutrophile <1.5 x109/L, Thrombocytes <100 x109/L.
12. Total-Serum-Bilirubin >1.5 x ULN (upper limit of normal) (except in patients with confirmed and documented Gilbert-Lereboullet-syndrome), ALT or AST >2.5 x ULN (>5 x ULN by liver metastases), Alkaline Phosphatase >2.5 x ULN (>4 x ULN by liver or bone metastases), Serumcreatinine > 2 x ULN
13. Pregnancy, nursing (a negative pregnancy test must be documented, and safe anticontraceptive measures during pre- and postoperative treatment must be implemented)
14. Lack of signed informed consent after informing the patient
15. Lack of willingness to keep and disclose personal medical data as part of the study