6 Combining anthracyclines with other therapies, such as trastuzumab (an antibody targeting HER-2), can provoke greater cardiotoxicity with depressed LVEF occurring in ≈18% to 34% of treated individuals, and severe, symptomatic heart failure in 2% to 4%.3,7 Additional clinical parameters are recognized to contribute to CCM, including female sex, extremes of age, and preexisting cardiac risk factors.2 Even when accounting for these factors, predicting individual susceptibility to CCM remains challenging. Here, ERBB2 is linked to cerebral cavernous malformation.