PIK3CA and megalodactyly: The identification of PIK3CA somatic mutations in syndromes with distinct, but partially overlapping, clinical findings, such as Fibroadipose hyperplasia or Overgrowth4, CLOVES syndrome5, macrodactyly and muscle hemihypertrophy6, Megalencephaly-Capillary Malformation7, and hemimegalencephaly8, suggested to group all of these syndromes and term them “PIK3CA-related overgrowth spectrum” (PROS)3.