Specifically, miR-1 showed significant predictive value in the ER-positive group (OR = 10.242, p = 0.001, 95% CI 2.689–51.593), PR-positive group (OR = 5.571, p = 0.002, 95% CI 1.907–17.855), HER2-positive group (OR = 4.444, p = 0.006, 95% CI 1.569–13.495), high Ki67 group (OR = 28, p < 0.001, 95% CI 5.4–197.624), large tumour size group (OR = 6.159, p = 0.001, 95% CI 2.094–20.091), lymph node metastasis group (OR = 8.306, p < 0.001, 95% CI 2.824–27.637), and grade III group (OR = 8.925, p < 0.001, 95% CI 2.618–35.382). This evidence concerns the gene ERBB2 and metastatic malignant neoplasm in the lymph nodes.