ERBB2 and breast cancer: However, based on positive findings from the HER2CLIMB trial in patients with HER2+ mBC, which did include patients with BM [16], the HER2 inhibitor tucatinib, in combination with capecitabine and trastuzumab, recently received FDA-approval for the treatment of patients with advanced unresectable or metastatic HER2+ breast cancer, including patients with BM [4].