We searched PubMed records published from Jan 1, 2009, to March 3, 2022, to identify publications directly relevant to the FAKTION clinical setting using the search terms “AKT” or “PI3K” or “mTOR” or “mTORC1” and “oestrogen receptor” and “breast cancer” and “metastatic” and “inhibitor” or “inhibition”. The gene discussed is PIK3CA; the disease is breast cancer.