That is why currently we have a complex and well-coordinated interdisciplinary therapy that uses genomic markers such as Breast Cancer Gene 1/2 (BRCA1, BRCA2) and Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha (PIK3CA), immunohistochemical markers like estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor receptor 2 (HER2) and immunomarkers like Programmed Death-Ligand 1 (PD-L1) and tumor-infiltrating lymphocytes to determine the most suitable treatment for our patients and greatly improving their overall success rates [8,9,10,11]. The gene discussed is ESR1; the disease is neoplasm.