ERBB2 and breast cancer: This is also evident in familial breast cancer, where the inheritance of a pathogenic germline driver mutation is also strongly related to the resulting tumour phenotype: ER-negative in BRCA1-associated tumours (with high frequency of TP53 mutations); ER-positive in BRCA2, ATM and CHEK2-associated tumours; HER2-positive in TP53-carriers; and E-cadherin negative and lobular growth pattern in CDH1-carriers [19,24,25,26,27,28,29].