The results of mRNA levels showed that the lymph node metastasis (4 ~ 9 or ≥ 10), MSH2 (OR 1.027, 95% CI 1.012 ~ 1.044, P < 0.05), PARP1 (OR 1.052, 95% CI 1.026 ~ 1.080, P < 0.05) were risk factors for postoperative metastasis of breast cancer. The gene discussed is MSH2; the disease is breast cancer.