Chew S, Carroll HK, Darwish W, et al. - Brain metastases (BM) develop in nearly 30% of breast cancer patients. The disease course, treatments and outcome for the patient cohort have been reported herein.

• Using electronic records from January 2015 to December 2020, clinicopathological data of 98 patients were retrieved.

• After BM development, systemic therapy was used in half of the patients and local therapy was used in 70%, but a prolonged overall survival (OS) was recorded only in the HER2 subgroup; this likely reflects central nervous system (CNS) activity of anti-HER2 drugs.

• The worst prognosis was recorded for triple negative breast cancer patients.

• Despite the small size of the cohort, 60% of HER2+ patients who received trastuzumab emtansine after BM development had OS > 1 year, which is encouraging for antibody drug conjugates and CNS activity.

• The burden of CNS disease was noted to be higher in patients who received whole brain radiotherapy (WBRT) with an OS of less than 3 months.