Hormone-receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer accounts for 65% of all metastatic breast cancer (MBC) cases. With the advent of CDK4/6 inhibitors, single-agent endocrine therapy (ET) is no longer the only first-line systemic treatment option for the vast majority of patients presenting without visceral crisis. Other endocrine-based treatment options are emerging in further lines, with the goal to delay the administration of chemotherapy as long as possible. The optimal sequence of treatment is unknown. We here present a review of the available treatments and propose a treatment algorithm taking into account the latest therapeutic developments.

(BELG J MED ONCOL 2021;15(1):20-33)