Brain Metastasis from HER2-Positive Breast Cancer: An Evolving Landscape

Summary Trastuzumab deruxtecan is a HER2-directed antibody–drug conjugate with ability to cross the blood–tumor barrier and activity on brain metastases. To test the activity of new drugs, patient-derived xenograft models from human brain metastases and phase 0 and window-of-opportunity trials are of utmost importance. See related article by Kabraji et al., p. 174