Metastatic breast cancer, also known as advanced or stage IV breast cancer, is the stage in breast cancer progression in which malignant cells from the primary tumor successfully create new tumors in distant organs. Patients diagnosed with advanced breast cancer, especially at a young age, have a lower 5‑y survival rate than those diagnosed at earlier stage. Therapy for metastatic breast cancer depends on the subtype of breast cancer, the evolution of breast cancer subtypes as metastases form, and the general medical condition of the patient, which can limit tolerance to therapies. As chemotherapy continues to improve through deliberative research on treatment of metastases in organs such as liver and bone, the site that lacks any significant clinical gains is the brain. Current treatments for brain metastases include surgery, radiotherapy, hormonal therapy. However there is a notable paucity of chemotherapeutic options. Despite the inherent challenges of effectively delivering drugs to the brain, to extend the lives of patients with brain metastases from breast cancer the treatment repertoire must be expanded.