ERBB2 and breast cancer: When examined by intrinsic subtypes, HR + HER-2 BC and HER2-enriched BC significantly correlated with SLNM, and TNBC also showed a similar tendency (HR + HER2-BC: p < 0.001, HER2-enriched BC: p = 0.047, TNBC: p = 0.053) (Table 3).