Hormone receptor-positive tumors represent the most common type of breast cancer and the type that accounts for the largest proportion of breast cancer deaths. Endocrine therapy (ET) represents the main treatment initiation strategy for these patients and is associated with significant clinical benefit in the majority of patients. A recent review published in Therapeutic Advances in Medical Oncology systematically summarized the optimal treatment strategies for hormone receptor-positive metastatic breast cancer based on the latest advances in endocrine therapy research. Medical Oncology summarizes the endocrine sequential therapy options for patients with HR-positive advanced breast cancer, as shown in the table below. Figure. Endocrine sequential treatment options for patients with HR-positive advanced breast cancer Chart Notes: ● Sequencing of treatment options within each text box does not represent a specific order of priority. ● Subsequent ET therapy should always take into account prior therapy and the duration and type of response to prior ET. ● Intrinsic or primary resistance was defined as recurrence within the first 2 years of adjuvant ET or disease progression within 6 months of starting ET in the treatment of advanced breast cancer. ● Acquired or secondary resistance was defined as recurrence after the first 2 years of adjuvant ET or disease progression more than 6 months after initiation of ET in the treatment of advanced breast cancer. These definitions, although imperfect or somewhat arbitrary, are useful for analyzing and stratifying patients in clinical trials. ● These recommendations apply to postmenopausal patients. ● These recommendations do not take into account drug accessibility and regulatory issues in different parts of the world. Note: ABC: advanced breast cancer; DFI: disease-free interval; AI: aromatase inhibitor; PFS: progression-free survival