Estrogen receptor (ER), progesterone receptor (PR), HER2, tumor grade, and genomic assays, along with tumor size, nodal status, and other disease-related factors such as the site and number of metastases, have all been shown to be associated with survival duration in patients with metastatic breast cancer (MBC) [1,2,3,4]. The gene discussed is ERBB2; the disease is neoplasm.