Several preclinical analyses have suggested how the presence of mutation in PI3KCA/AKT/mTOR (phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin) pathway as well as PTEN (phosphatase and tensin homolog) gene loss detected on primary BC tissue correlates with everolimus benefit [4, 5]. The gene discussed is MTOR; the disease is breast cancer.