A Case Report of an Emergency Hypertensive Episode During Trastuzumab Therapy

Human epidermal growth factor receptor 2 (HER2+) targeted therapies, such as trastuzumab emtansine, has been shown to have a significant positive effect on the outcome of breast cancer. Rarely, this therapy can cause adverse cardiovascular effects such as cardiac dysfunction, arrhythmias and hypertension. We report a case of a 60-year-old woman who presented to the emergency department with an episode of hypertensive emergency. She had been recently diagnosed with hypertension which was found to be poorly controlled. The recent administration of trastuzumab together with this hypertensive episode led us to suspect trastuzumab as the cause for this rise in her blood pressure. With this case we intend to raise awareness of hypertension, a potentially preventable condition, as an adverse effect of human epidermal growth factor receptor 2 targeted therapies such as trastuzumab. Additionally we propose an appropriate and careful management of arterial hypertension among those receiving this first-in-class drug.