ERBB2 and cancer: In clinical practice, our model is unlikely to be applied to very aggressive subtypes such as HER2-overexpressed and TNBC, but to subtypes that have a more “intermediate” prognosis such as luminal B. Treatment of luminal B cancers is typically based on an in-depth list of criteria, including size, lymph node involvement, grade, Ki67 status and a low personal risk of relapse determined by other gene expression signature models such as OncotypeDX [50].