This is a Prospective, Single-Arm, Observational, Real-World Study. The purpose of this study is to evaluate the safety and efficacy of pyrotinib combined with trastuzumab and pertuzumab for maintenance therapy in HER2-positive advanced breast cancer in the real-world setting.
Age ≥ 18 years, male or female.
Histologically or cytologically confirmed HER2-positive advanced breast cancer (IHC 3+, or IHC 2+ with ISH amplification), with known HR status.
Have unresectable locally advanced or metastatic disease. If recurrent (after [neo]adjuvant therapy), must be at least 6 month treatment free from any trastuzumab and pertuzumab received in the early breast cancer setting for advanced HER2+ disease.
Have received 4-8 cycles of pre-study induction therapy including only trastuzumab, pertuzumab, and taxane as first-line of therapy for the treatment of advanced breast cancer prior to study enrollment. Participants are eligible provided they are without evidence of disease progression following completion of induction therapy.
Other malignancy diagnosed within 5 years prior to enrollment.
Prior treatment with any tyrosine kinase inhibitor targeting HER2 and/or epidermal growth factor receptor (EGFR) including pyrotinib, lapatinib, tucatinib, neratinib, and afatinib.
Patients who are difficult or unable to be followed-up.
Other reasons that, in the investigator's judgment, make the patient unsuitable for participation in this study.