ERBB2 and neoplasm: K-M curves and log-rank tests were applied to determine OS and DFS.<h4>Results</h4>Compared with HER2-0 and HER2-high patients, the HER2-low group had a greater proportion of members in the N1-2 group and with grade I-II disease, a tumor size ≤ 20 mm, a Ki-67 index ≤ 14%, and invasive cancer.