KRT5 and breast cancer: Six subtypes were identified in a large dataset of 587 TN cases, including two subtypes resembling the basal subtype [28], Thus, to define a more homogeneous class of basal breast cancer while avoiding a definition based on negative staining, more sophisticated definitions have been proposed, which include positive staining for one or several basal/myoepithelial markers such as CK5, CK14, CK17, P-cadherin, KIT, EGFR and/or others.