Compared to ALND, axillary were more likely to be conserved when early N1 breast cancer was T1 (58.35% vs. 48.02%, p < 0.001), hormone receptor positive (83.91% vs. 75.70%, p < 0.001), HER2 negative (49.03% vs. 26.57%, p < 0.001), or treated with partial mastectomy (49.03% vs. 26.57%, p < 0.001). This evidence concerns the gene ERBB2 and breast cancer.