PIK3CA and cancer: Both CNS and HLT cancers had no obviously superior initiators, with CIC (13.6%), PIK3CA (10.1%) and TP53 (10.0%) as the top three initiators for the former, and TP53 (14.9%), NPM1 (10.4%) and MLL2 (9.9%) as the top three initiators for the latter.