ERBB2 and lymph node disorder: In the 3+ Her-IHC group with clinical lymph node involvement (>cN0, 3+ Her2-IHC, n = 102), most cases were classified as pN0 (86.27%, n = 88) after pathological examination of the resection specimen, and in the 2+ Her-IHC group with clinical lymph node deposits (>cN0, 2+ Her2-IHC n = 38), most cases were classified as pN0 (60.52%, n = 23) after pathological examination, suggesting a higher control of lymph node diseases in 3 + Her2-IHC cases (p = 0.0018, Fisher’s exact test).