Adjuvant chemotherapy administration was significantly associated with pN1mi (OR=9.647, 2.01-46.22, p=0.005) and HR-negative Her2-positive subtype (OR=2.790, 1.12-6.94, p=0.027), without significant association with age 75-80 (OR=0.631, 0.32-1.23, p=0.179), pN0(i+), HR-positive Her2-positive BC and with LVI. The gene discussed is ERBB2; the disease is breast cancer.