Treatment of Dalpiciclib Combined With Pyrotinib for Trastuzumab-sensitive HER2+ Advanced Breast Cancer(DAP-Her-02)

Inclusion Criteria

• •1. Premenopausal / perimenopausal / postmenopausal women who aged ≥ 18 years
• •2. Suffering from non resectable locally advanced recurrent breast cancer or metastatic breast cancer
• •3. group A: Women who have breast cancer histopathologically confirmed by positive estrogen receptor (ER; \>10%), positive progesterone receptor (PR; \>1%), and positive human epidermal growth factor receptor 2 (HER2) according to the 2018 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) human epidermal growth factor receptor 2 (HER2) guideline. The pathological laboratory confirmed that the immunohistochemical (IHC) score was 3 +, or 2 +, and the in situ hybridization (ISH) test was positive (ISH amplification rate ≥ 2.0); (New) the end of trastuzumab treatment in the adjuvant treatment stage \> 12 months, recurrence and metastasis, or no trastuzumab treatment in the early stage; No adjuvant endocrine therapy or postoperative adjuvant endocrine therapy \> 24 months; Premenopausal or perimenopausal patients need to be combined with ofs (OFS includes bilateral ovariectomy or GnRHa drugs); group B: Women who have breast cancer histopathologically confirmed by negative estrogen receptor (ER), negative progesterone receptor (PR; \<1%), and positive human epidermal growth factor receptor 2 (HER2) according to the 2018 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) human epidermal growth factor receptor 2 (HER2) guideline. The pathological laboratory confirmed that the immunohistochemical (IHC) score was 3 +, or 2 +, and the in situ hybridization (ISH) test was positive (ISH amplification rate ≥ 2.0); (New) the end of trastuzumab treatment in the adjuvant treatment stage \> 12 months, recurrence and metastasis, or no trastuzumab treatment in the early stage;
• •4. No previous systematic treatment for advanced diseases
• •5. at least one measurable lesion or only bone metastasis according to RECIST 1.1.
• •6. Eastern Cooperative Oncology Group (ECOG) performance status 0～1.
• •7. The patient must be able to swallow oral drugs
• •8. The functional level of organs must meet the following requirements:
• •a) Bone marrow function i) Absolute neutrophil count（ANC）≥1.5×109/L (no use of growth factor within 14 days) ii) Platelet count（PLT）≥100×109/L (no corrective treatment within 7 days) iii) Hemoglobin level（Hb）≥100 g/L (no corrective treatment within 7 days) b) Liver and kidney function i) Total bilirubin（TBIL）≤1.5 upper limit of normal value (ULN) ii) Alanine transaminase (ALT) and aspartate transaminase (AST) ≤3×ULN iii) Blood urea nitrogen (BUN) and creatinine ≤1.5×ULN and creatinine clearance≥50 mL/min (Cockcroft-Gault formula); c) Color Doppler echocardiography: Left ventricular ejection fraction ≥50% d) 12-lead electrocardiography: QTc interval ≤480 ms
• •9. Volunteers to participate in the study, provision of signed informed consent, good compliance and willingness to cooperate with follow-ups.