In breast cancer, the fraction of ALDH1-positive cells correlates with the molecular subtypes, being highly expressed in the basal-like and HER2 subtypes, but not with other patho-biologic features [13] and is predictive of clinical outcome in breast cancer series in different clinical settings [12,14], even if such a finding is not univocal [13]. Here, ERBB2 is linked to breast carcinoma.