Combination of palbociclib with adjuvant endocrine therapy for treatment of hormone receptor-positive and human epidermal growth factor receptor 2-negative metastatic breast cancer: An experience at two cancer centers in Saudi Arabia.

The addition of palbociclib (a cyclin-dependent kinase 4/6 inhibitor) to endocrine therapy (ET) has been shown to significantly improve progression-free survival (PFS) and overall survival (OS) among patients with hormone receptor-positive (HR) advanced breast cancer. The current study presents the local experience of using palbociclib at two cancer centers in Saudi Arabia. Electronic data of patients with metastatic HR and human epidermal growth factor receptor 2-negative breast cancer who progressed after prior ET and received at least one cycle of palbociclib plus ET, were retrospectively reviewed.