PIK3CA and breast cancer: Furthermore, in the plasmaMATCH trial, which investigated responses to capivasertib therapy, among others, in patients with advanced breast cancer, PPA for ctDNA digital polymerase chain reaction versus tissue-based NGS was 88.2% for PIK3CA (n = 77) and 88.9% for AKT1 (n = 76) mutations defined as actionable [36].