Enrollment subjects must have a pathological diagnosis of HER2-positive primary invasive breast cancer with an immunohistochemistry (IHC) score of 3 +, or 2 + and HER2 gene amplification by in situ hybridization (ISH) (ratio of HER2/CEP17 ≥ 2.0).
The invasive tumor had to measure no more than 3cm and with histologically confirmed lymph node-negative or one lymph node micrometastasis (T ≤ 3 cm, N0/N1mi, M0).
Tumor should has known ER/PR hormone receptor status.
All patients must be women above18 years old with Eastern Cooperative Oncology Group score 0 to 1.
Adequate hematopoietic function and organ function as defined as follows: neutrophil count ≥ 1.5 x 109/L; Platelet count ≥ 90 × 109/L; Hemoglobin ≥ 90 g/L; total bilirubin ≤ 1.5 × ULN; alanine transaminase (ALT) and aspartate transaminase (AST) ≤ 3 × ULN; serum creatinine Cr ≤ 1.5 × ULN and creatinine clearance ≥ 50 mL/min (Cockcroft-Gault formula).
left ventricular ejection fraction (LVEF) ≥ 50% and Electrocardiogram Fridericia-corrected QT interval (QTcF) ≤ 480 ms.
Provide written informed consent.
You may not be if
Clinical or radiologic evidence of local or regional recurrence of disease or metastatic disease prior to or at the time of study entry.
Previous treatment with chemotherapeutic drugs, or tyrosine kinase inhibitors targeting HER2 (lapatinib, neratinib or pyrotinib, etc.).
Other malignancies within the past 5 years, excluding cured cervical carcinoma in situ, cutaneous basal cell carcinoma, or cutaneous squamous cell carcinoma.
Inability to swallow, chronic diarrhea, or intestinal obstruction.
Known to be allergic to the drug components.
Have a history of immunodeficiency, including HIV positive, HCV positive, active viral hepatitis B or other immunodeficiency diseases.
Have a history of organ transplantation.
Pregnant, lactating female patients, or female patients who are unwilling to take effective contraceptive.
