PIK3CA and overgrowth syndrome: Recent study identified that somatic and mosaic gain-of-function mutations of the phosphatidylinositol-4,5-bisphosphate 3-kinase Catalytic Subunit Alpha (PIK3CA) gene were found in FAVA, and FAVA belongs to the spectrum of PIK3CA-related overgrowth syndromes (PROS) [5–7].