ERBB2 and invasive ductal breast carcinoma: FISH was applied to a discovery cohort of 82 sporadic oestrogen receptor-negative invasive ductal carcinomas: composed of 42 BLBC (negative for ERα, PR, HER2 and positive for CK5/6, CK14 or EGFR), 14 triple-negative non-BLBC (negative for Erα, PR, HER2, CK5/6, CK14 and EGFR) and 26 HER2-Enriched (negative for Erα and PR, positive for HER2) samples [11].