A number of studies on breast cancer patients have determined that the following factors are associated with increased risk for brain metastasis (reviewed here [39, 40]): younger age, premenopausal status, invasive ductal carcinoma (IDC) histological type, estrogen receptor negative (ER−), p53 mutations, and EGFR overexpression. This evidence concerns the gene EGFR and invasive ductal breast carcinoma.