As shown in Table 1, the clinical and histopathological variables including age, menopause, tumor size, HER2 status, and Ki-67 status between patients with and without SLN metastasis had no significant difference (all p > 0.05), while there were significant differences in ER and PR status between these two groups (both p < 0.05). The gene discussed is ESR1; the disease is neoplasm.