PIK3CA and lymphangioleiomyomatosis: In contrast to these settings where promoting VEGFC/VEGFR3-mediated lymphangiogenesis is beneficial, diseases including lymphangioleiomyomatosis (LAM) [105], Gorham-Stout Disease (in which the lymphatics invade bone) [106] and lymphatic malformations driven by PIK3CA mutations [107] are characterised by elevated VEGFC- and VEGFD-initiated VEGFR3 signalling.