Nearly all activating PIK3CA mutations in IntClusts10 (median CCF=1, interquartile range (IQR)=1–1, 26 mutations) and IntClust9 (median=1, IQR=0.98–1, 49 mutations) were present at CCFs close to 1, whereas some PIK3CA mutations in IntClust3 tumours were present in lower CCFs (median=0.96, IQR=0.75–1, 215 mutations). This evidence concerns the gene PIK3CA and neoplasm.