BRCA1 and breast carcinoma: Though BRCA1/2 PV breast cancers generally have greater immune infiltration [8] and simultaneously a more immunosuppressive microenvironment than sporadic breast cancers, sporadic breast cancers with high degrees of homologous repair deficiency can present phenotypically similarly to BRCA1/2 PV breast cancers with increased numbers of infiltrating lymphocytes [71], as well as decreased immune cytotoxicity and thus higher degrees of immune evasion [72].