PIK3CA and famililal cerebral cavernous malformations: Also, in vivo, other types of PI3K‐related vascular malformations such as Pik3ca‐driven lymphatic malformations and cerebral cavernous malformations, and hereditary haemorrhagic telangiectasia‐like arteriovenous malformations rely on growth factor signals to be induced and expand (Garrido‐Martin et al, 2014; Martinez‐Corral et al, 2020; Mäkinen et al, 2021; Ren et al, 2021).