ERBB2 and breast cancer: Point mutations and CNAs displayed high heterogeneity among subtypes: TP53 mutations and TP53 and TP2A amplifications were more frequently observed among TNBC; as expected, ERBB2 amplifications are almost exclusively observed among HER2+ tumors; PIK3CA mutations, ZNF703, CCND1, PAK1, and FGFR1 amplifications were more frequently observed among Lum/HER2- breast cancers [57].