ERBB2 and breast cancer: This implies there is a substantial revenue loss for the treating institution if HER2-positive patients are not identified and treated appropriately, considering most patients are able to obtain insurance with a breast cancer diagnosis since the passing of the Affordable Care Act.18 In their model-based study, Garrison et al. addressed the cost effectiveness of correctly diagnosing HER2-positive breast cancer due to the clinical benefit of the addition of trastuzumab to adjuvant chemotherapy.