When the data was pooled, respectively, there were no significant associations between HER2 amplification and gender (P = 0.49), tumor location (P = 0.12), differentiation (P = 0.55), lymph node metastasis (P = 0.76), T stage (P = 0.16), and TNM stage (P = 0.89) (Table 2). This evidence concerns the gene ERBB2 and metastatic malignant neoplasm in the lymph nodes.