In advanced, HER2+ breast cancer, the addition of pertuzumab to trastuzumab and docetaxel increased progression-free survival from 12.4 to 18.5 months (HR 0.62; 95% CI 0.51–0.75; p < 0.001) [13], and overall survival from 40.8 (95% CI 35.8–48.3) to 56.5 (95% CI 49.3 – not reached) months [14]. Here, ERBB2 is linked to breast cancer.