Pyrotinib in Combination With Letrozole in Patients With HER2-Positive, ER-Positive Metastatic Breast Cancer

Exclusion Criteria

• •1. Central nervous system metastasis;
• •2. patients with Visceral crisis;
• •3. Unable to swallow, chronic diarrhea and intestinal obstruction, there are many factors affecting drug use and absorption;
• •4. received radiotherapy, hormone therapy, chemotherapy, surgery (excluding local puncture) or molecular targeted therapy for advanced or metastatic disease;
• •5. received radiotherapy, chemotherapy, surgery (excluding local puncture) or molecular targeted therapy within 4 weeks prior to randomization;
• •6. Received hormone therapy within 2 weeks prior to randomization;
• •7. Participated in other clinical trial within 4 weeks prior to randomization;
• •8. Previous or ongoing use of HER2-targeted tyrosine kinase inhibitors (lapatinib, neratinib or pyrotinib);
• •9. Other malignancies within 5 years, except for cured skin basal cell carcinoma,carcinoma in-situ of uterine cervix and squamous-cell carcinoma;
• •10. Receive other anti-tumour therapy at the same time;
• •11. History of immunodeficiency, including HIV positive, HCV, active hepatitis B, or other acquired, congenital immunodeficiency disorders, or organ transplantation, is known;
• •12. History of any kind of Heart disease;
• •13. All female patients in pregnancy or breastfeeding period, fertile women with positive baseline pregnancy tests;
• •14. Evidence of significant medical illness that will substantially increase the risk on the participation or completion of the study in the investigator's judgment. Examples included, but not limited to, hypertension, severe diabetes, etc;
• •15. History of neurological or psychiatric disorders, including epilepsy or dementia;