ERBB2 and neoplasm: As an incidental finding that validates the normal mammary epithelial HR groups in Santagata S. et al. in [27], Huss et al. performed the nuclear and cytoplasmic staining of tumor tissue microarrays (TMA) and reported that VDR+ expression is highest in the order LumA > LumB > HER2 and the lowest in TNBC [72].