ERBB2 and breast cancer: Wen et al. [16] found that the HER2-enriched and TNBC subtypes were associated with significantly higher 5-year LRR rates, lower 5-year LRRFS rates, and poorer 5-year BCSS rates in pT1-2N1M0 breast cancer patients who did not undergo PMRT, compared with the luminal A subtype.