ERBB2 and neoplasm: Notably, a substantial correlation between NSLN metastasis and tumor size (OR 1.93, 95% CI 1.15–3.22, P = 0.0126), HER2 expression status (OR 2.05, 95% CI 1.16–3.63, P = 0.0134), LVI (OR 6.11, 95% CI 3.62–10.32, P < 0.0001), and the number of positive SLNs (OR 4.50, 95% CI 2.72–7.46, P < 0.0001) was established.