Thus far, both the Food and Drug Administration (FDA) and European Medicines Agency (EMA) have approved everolimus for the therapeutic management of hormone-receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer (combined with exemestane); pancreatic neuroendocrine tumors; renal cell carcinoma (RCC); and the tuberous sclerosis complex (TSC) [5]. The gene discussed is ERBB2; the disease is breast cancer.