ERBB2 and breast cancer: 378 (52%) of the 726 breast cancer cases had the variant, with similar prevalence between the subtypes (p = 0.392): Luminal A (279 [54%] of 519 cases), Luminal B (37 [44%] of 84 cases), HER2 (21 [53%] of 40 cases) and triple negative breast cancer (41 [49%] of 83 cases).