Only systemic disease (P<0.001) remained an independent prognostic factor of brain metastases, whereas tumor grade (P=0.095), axillary lymph node metastases (P=0.113) and serum HER2 (P=0.894) were not statistically significant in the multivariate analysis. The gene discussed is ERBB2; the disease is metastatic malignant neoplasm in the lymph nodes.