This strategy is defined as matched therapy: a therapeutic regimen including an agent (either as a single agent or as a part of a combination regimen) that is known to directly inhibit a specific mutation, and/or to inhibit its key downstream pathways, such as treatment with a PI3K inhibitor, an mTOR inhibitor, or these agent-based regimens for a cancer patient carrying a PIK3CA mutation and/or PTEN loss/mutation [20]. The gene discussed is PIK3CA; the disease is cancer.