Factors associated with developing and surviving brain metastases in patients with breast cancer: a multi-center experience

BCBM is a heterogeneous population with variable outcomes. This analysis suggests that several factors influence the development and outcome after BCBM with HR+/HER2- subgroup having the longest median time to develop BM compared to other subgroups. Survival after BCBM is impacted by age, performance status and overall disease burden, as well as the use of novel targeted therapies suggesting the feasibility to overcome the historical blood brain barrier to systemic treatment benefit from chemotherapy. Brain surgery and Radiation modalities also play an important role in improving long term outcome. These results support updating current prognostic models, such as the Breast-GPA, by integrating treatment exposures, shifting from static baseline scores to dynamic, treatment-informed prognostication.