This study is a multicenter, single-arm, prospective, open clinical study to evaluate the efficacy and safety of pyrotinib in combination with trastuzumab, albumin paclitaxel, and carboplatin in neoadjuvant therapy for ER+/HER2+ early or locally advanced breast cancer.

Inclusion Criteria:

• Newly treated female patients aged ≥18 years and ≤75 years;

• ECOG score 0~1;

• Pathologically diagnosed as HER2-positive breast cancer patients with early or locally advanced tumor stage, primary tumor diameter T≥2cm or lymph node positive;

• Hormone receptor status (ER and PgR) is known, where ER≥10%

• Normal function of major organs:

  1. The standard of blood routine examination should meet: ANC ≥1.5×109/L; PLT≥90×109/L; Hb ≥90g/L
  2. Biochemical examination should meet the following standards: TBIL≤ the upper limit of normal value(ULN); ALT and AST≤1.5 times the upper limit of normal (ULN); Alkaline phosphatase ≤2.5 times the upper limit of normal (ULN); BUN and Cr≤1.5×ULN and creatinine clearance ≥50 mL/min (CockcroftGault formula);
  3. Cardiac color ultrasound and echocardiography: left ventricular ejection fraction(LVEF≥55%)
  4. Fridericia calibrated QT interval (QTcF) for 18-lead ECG <470 ms;

• For female patients who are not menopausal or have not been surgically sterilized: consent to abstinence or use of an effective contraceptive method during treatment and for at least 7 months after the last dose in the study treatment;

• Volunteer to join the study and sign the informed consent.

Exclusion Criteria:

• Stage IV (metastatic) breast cancer;

• Inflammatory breast cancer;

• Previous antitumor therapy or radiation therapy for any malignancies, excluding cured cervical carcinoma in situ, basal cell carcinoma, or squamous cell carcinoma;

• Also receiving antitumor therapy in other clinical trials, including endocrine therapy, bisphosphonate therapy, or immunotherapy;

• Had a major surgery not related to breast cancer in the 4 weeks prior to enrollment, or had not fully recovered from such surgery;

• Serious heart disease or discomfort, including but not limited to the following:

  • History of heart failure or systolic dysfunction (LVEF < 50%)
  • High-risk uncontrolled arrhythmias, such as atrial tachycardia, resting heart rate >100 bpm, significant ventricular arrhythmias (such as ventricular tachycardia), or higher-grade atrioventricular block (i.e. Mobitz II second- degree atrioventricular block or third-degree atrioventricular block

• Inability to swallow, intestinal obstruction, or other factors affecting the use and absorption of the drug;

• Known allergic history of the drug components of this protocol; A history of immunodeficiency, including HIV testing positive, or other acquired, congenital immunodeficiency diseases, or a history of organ transplantation;

• Women who are pregnant or nursing, women who are fertile and have a positive baseline pregnancy test, or women of childbearing age who are unwilling to use effective contraception throughout the trial period and within 7 months after the last study medication;

• Have a serious concomitant condition or other comorbid condition that interferes with planned treatment, or any other condition in which the investigator deems the patient unsuitable for participation in the study.