PIK3CA and cancer: Within cancer types, commonly mutated genes included TP53 (41.7%), PIK3CA (38.2%), ESR1 (29.1%), BRCA2 (18.5%), NF1 (17.3%), ATM (14.6%) and APC (11.8%) in breast cancer, TP53 (59.8%), KRAS (21.6%), EGFR (18.3%), and ATM (14.6%) in lung cancer, and TP53 (69.4%), APC (66.3%), and KRAS (36.7%) in colorectal cancer (Fig. 3b).