Real-world Study of Pyrotinib-containing Regimens of Advanced HER2-positive Breast Cancer

Inclusion criteria

• Aged ≥ 18 years old;
• Histopathologically confirmed HER2-positive inoperable locally advanced or metastatic breast cancer;
• Patients with first-line or second-line advanced disease:

First-line advanced disease: no prior systemic therapy for locally advanced or metastatic disease. For patients who received neoadjuvant or adjuvant therapy, the disease-free interval (DFI) after the completion of the last chemotherapy or HER2-targeted therapy was more than 12 months; Second-line advanced disease: prior treatment with taxane combined with trastuzumab, with or without pertuzumab, in the advanced setting; or recurrence occurring during neoadjuvant/adjuvant therapy, or a disease-free interval (DFI) of ≤ 12 months after completion of the last neoadjuvant/adjuvant chemotherapy and HER2-targeted therapy;

• Planned to receive pyrotinib-containing regimen, and judged by investigators based on clinical practice to have potential subsequent treatment with Ruikang trastuzumab after failure of pyrotinib-containing therapy;
• Traceable medical records available throughout the treatment period.

Exclusion criteria

• Failure to sign the informed consent form;
• Pregnant or lactating females;
• Patients participating in any interventional clinical trial involving investigational drugs or marketed drugs at enrollment;
• Other conditions deemed ineligible for enrollment by the investigator's judgment.