This is a randomized, double-blind multicenter Phase III study for evaluating the efficacy and safety of neoadjuvant pyrotinib and trastuzumab plus docetaxel and Carboplatin versus placebo and trastuzumab plus docetaxel and Carboplatin given as neoadjuvant treatment in HER2 positive early stage or locally advanced breast cancer.

The investigators hypothesized that the experimental group (Pyrotinib+Trastuzumab+Docetaxel+ Carboplatin) could have a higher Pathological Complete Response (pCR) rate than the control group (Placebo +Trastuzumab+Docetaxel+ Carboplatin) in neoadjuvant chemotherapy.

It is proposed that 100 participants will be enrolled in this study. The target population is women with early breast cancer (stage of T1-4N0-3M0) who are eligible for primary systemic therapy.

The primary objective of the trial is to determine the pCR rate. The secondary objective of the trial is to determine the Event-free survival(EFS), Disease-free Survival (DFS), Distance Disease-free Survival (DDFS), Objective Response Rate (ORR) rate.

Inclusion Criteria:

1. female patients, 18 years ≤ age ≤ 80 years；
2. Performance Status- Eastern Cooperative Oncology Group (ECOG) 0-1
3. Histologically confirmed invasive breast cancer（early stage or locally advanced）
4. HER2 positive (HER2+++ by IHC or FISH+)
5. Known hormone receptor status.
6. Cardiovascular: Baseline left ventricular ejection fraction (LVEF)≥55% measured by ECHO
7. Signed informed consent form (ICF)

Exclusion Criteria:

1. Metastatic disease (Stage IV) or inflammatory breast cancer
2. Previous or current history of malignant neoplasms, except for curatively treated: Basal and squamous cell carcinoma of the skin, Carcinoma in situ of the cervix.
3. Clinically relevant cardiovascular disease: Known history of uncontrolled or symptomatic angina, clinically significant arrhythmias, congestive heart failure, transmural myocardial infarction, uncontrolled hypertension ≥180/110);
4. Unable or unwilling to swallow tablets.