ERBB2 and cancer: TP53 remained largely unaltered in the HR + /HER- subtype (14.1%), but TP53 mutations were enriched in both HR + /HER2 + and HER2 + cancers (23.1%, 33.3%) (Fig. 1a), with the highest frequency of TP53 mutations (50.0%) in TNBC tumors.