ERBB2 and breast cancer: Interestingly, NR patients showed a significantly higher risk of relapse than PR patients in all the four breast cancer subgroups: HR of NR patients was 12.898 (95 % CI 1.285–129.437, P = 0.030), 4.224 (95 % CI 1.088–16.394, P = 0.037), 5.044 (95 % CI 1.555–16.366, P = 0.007), and 4.206 (95 % CI 1.121–15.786, P = 0.033) in the LA, LB, HER2, and TNBC groups, respectively.