Attempts have been made to develop a simple IHC-based classifier for luminal and basal phenotypes in non-muscle invasive BC (NMIBC) as well, by using GATA3, CK20, ER, Uroplakin II, HER2, and CK5/6, CD44, respectively, with conflicting results so far [24]. The gene discussed is KRT5; the disease is breast cancer.