Furthermore, real-time monitoring of tumor biology by ctDNA, as was demonstrated in PALOMA-3 [32, 33], may be a reasonable option for selecting optimal therapy depending on tumor characteristics (e.g., detection of the PIK3CA mutation would result in the selection of a PI3K inhibitor, such as buparlis or alpelisib [68]). The gene discussed is PIK3CA; the disease is neoplasm.