Somatic PIK3CA mutations in seven patients with PIK3CA‐related overgrowth spectrum

Somatic mutations in PIK3CA cause many overgrowth syndromes that have been recently coined the “PIK3CA‐Related Overgrowth Spectrum.” Here, we present seven molecularly confirmed patients with PIK3CA‐Related Overgrowth Spectrum, including patients with Congenital Lipomatous Overgrowth, Vascular Malformations, Epidermal Nevi, Scoliosis/Skeletal and Spinal syndrome, Klippel–Trenaunay syndrome, lymphatic malformation and two with atypical phenotypes that cannot be classified into existing disease categories. The literature on PIK3CA‐Related Overgrowth Spectrum, suggests that PIK3CA c.1258T>C; p.(Cys420Arg), c.1624G>A; p.(Glu542Lys), c.1633G>A; p.(Glu545Lys), c.3140A>G; p.(His1047Arg), and c.3140A>T; p.(His1047Leu) can be identified in approximately 90% of patients without brain overgrowth. Therefore, droplet digital polymerase chain reaction targeting these mutation hotspots could be used as the first‐tier genetic test on patients with PIK3CA‐Related Overgrowth Spectrum who do not have signs of overgrowth in their central nervous system. © 2017 Wiley Periodicals, Inc.