PIK3CA in HER2+ BC and pCR Trial

Inclusion Criteria:

* Written informed consent.
* Age older than 18 years.
* Unilateral or bilateral primary carcinoma of the breast, confirmed histologically by core biopsy.
* Tumor lesion in the breast with a palpable size of ≥ 2 cm and/or ≥ 1.5 cm by ultrasound or magnetic resonance imaging (MRI). In case of inflammatory carcinoma the extent of inflammation can be used as measurable lesion.
* American Joint Commission on Cancer stage II or III invasive breast cancer.
* Known estrogen (ER)- and progesterone (PgR)-receptor negative or positive tumors.
* Known HER-2/neu positive tumors, defined as HercepTest IHC 3+ or SISH+.
* Patients suitable for neoadjuvant chemotherapy
* Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤2 or Karnowsky performance status index at least 80%.
* Normal cardiac function must be confirmed by ECG and cardiac ultrasound (LVEF or shortening fraction) within 1 month prior to registration.
* Laboratory requirements:

  * Hematology: Absolute neutrophil count (ANC) ≥ 1.5 x 109/L, platelets ≥ 100 x 109/L, Hemoglobin ≥ 10 g/dL.
  * Hepatic function: Total bilirubin \< 1 x UNL, ASAT (SGOT) and ALAT (SGPT)≤ 2.5 x UNL, Alkaline phosphatase ≤ 5 UNL. Patients with ASAT and / or ALAT \> 1.5 x UNL associated with alkaline phosphatase \> 2.5 x UNL are not eligible for the study.
  * Renal function: Creatinine ≤ 2 mg/dL, \< 1,25 UNL (or the calculated creatinine clearance ≥ 60 mL/min).
  * Paraffin tumor tissue block made available.
  * Availability to provide the set up of the histological preparations for molecular analysis.
  * Negative pregnancy test (urine or serum).
  * Patients must be available and compliant for treatment and follow-up.

Exclusion Criteria:

* Patients candidate for adjuvant chemotherapy.
* Evidence of distant metastasis.
* Prior chemotherapy for any malignancy.
* Prior radiation therapy for breast cancer.
* Pregnant or lactating patients.
* Inadequate general condition.
* Previous malignant disease.
* Known or suspected congestive heart failure (\>NYHA I) and/or coronary heart disease, angina pectoris requiring antianginal medication, previous history of myocardial infarction, evidence of transmural infarction on ECG, un- or poorly controlled arterial hypertension, rhythm abnormalities requiring permanent treatment, clinically significant valvular heart disease.
* History of significant neurological or psychiatric disorders that would prohibit the understanding and giving of informed consent.