Clinical Outcomes of Patients with HER2 Positive Metastatic Breast Cancer to the Brain, with First-Line Trastuzumab, Pertuzumab and Chemotherapy, in a Real-World Setting.

Background: In this observational study, we analyzed the treatment patterns and clinical outcomes of patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) who developed brain metastases during their disease in a 2.7 million-member public health-provider in Israel.

Methods: Newly diagnosed patients with mBC who initiated first-line treatment between January 2013 and June 2021 were identified.