ERBB2 and breast cancer: In summary, this single-arm, multicenter, Phase II study in patients with active HER2-positive breast cancer brain metastases (defined as CNS PD following prior radiation therapy), demonstrated that high-dose trastuzumab (6 mg/kg i.v. every week) combined with 3-weekly pertuzumab (given in standard i.v. dose and schedule) was associated with a high rate of clinical benefit, including radiographic stability and maintenance of QoL.