Through the univariate regression analysis of leukopenia, five univariate factors had statistical significance (p < 0.1), including the baseline levels of WBC before treatment (p < 0.001), different G-CSF types (p1 = 0.006, p2 = 0.019), surgical method (p = 0.017), lymph node metastasis (p1 = 0.033, p2 = 0.054), and use of Herceptin (p = 0.077) (Table 1). The gene discussed is CSF3; the disease is Decreased total leukocyte count.