The protein kinase B-phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha-phosphatase and tensin homolog (PI3K/AKT/PTEN) pathway, a tumor molecular signaling pathway in breast cancer, is a major signaling pathway in various types of cancer that contributes to tumor development and progression [5]. The gene discussed is PIK3CA; the disease is breast cancer.