BRCA1 and cancer: There has been only one study so far that has characterised the immunohistochemical features of familial non-BRCA1/2 cancers: Palacios and colleagues [18] studied immunohistochemical staining and histopathology and compared 37 non-BRCA1/2 cancers with 20 BRCA1-associated and 18 BRCA2-associated cancers, and also with unselected control cancers.