Correlating these driver mutations to clinical BC patient outcome showed that functional: (1) PIK3CA mutations in ER+ tumors were linked to lower tumor grade, (2) CBFB and GATA3 mutations were enriched for younger age patients, (3) KTM2C/MLL and CDH1 mutations occurred in older patients and (4) TP53 somatic mutations were linked to increased tumor grade irrespective of ER status [93]. This evidence concerns the gene PIK3CA and breast cancer.