PIK3CA and vascular malformation: Of the 34 children, pathogenic mutations were found in 5 (including the bilateral HMEG patient): (1) PIK3CA mutation in the bilateral HMEG, (2) PIK3CA mutation in HMEG with linear epidermal nevus, (3) PIK3CA mutation in a localized FCD IIa, (4) AKT3 mutation in HMEG with cutaneous vascular malformations and unilateral ocular enlargement, and (5) germline PTEN mutation with HMEG.