Additionally, activating KRAS pathogenic variants have also recently been described as a cause of aberrant vascular development, vascular malformation, and lymphatic anomalies including lymphedema, chylothorax, macrocystic lymphatic malformation, lymphangiectasia, and Gorham-Stout disease (10–13, 34, 40, 42–44). The gene discussed is KRAS; the disease is macrocystic lymphatic malformation.