ERBB2 and breast cancer: Intrinsic subtype distribution, assessed using PAM50 subtype predictor9 on 66 pretreatment BC biopsies, was: Luminal-A 39% (N = 25), Luminal-B 36% (N = 24), Basal-like 18% (N = 12), and HER2-E 8% (N = 5).