Syndromic vascular malformations related to the PIK3CA and RAS pathways: A clinical and imaging review

Vascular malformations are a complex and diverse group of disorders. They may enlarge with time, impair quality of life, and even be fatal. While many are sporadic, others are part of inherited syndromes; several gene mutations responsible for vascular anomalies have been identified. The PI3K/AKT/mTOR and RAS/MEK/ERK cascades have been extensively studied, and new molecular agents targeting these cascades are being developed. Diagnostic imaging findings are increasingly used to guide genetic testing, and in some cases, pathognomonic imaging characteristics can lead to a specific diagnosis. We review each of the representative syndromes associated with PIK3CA and RAS cascades, with updates of the latest in clinical and imaging information. •While many vascular malformations are sporadic, others are part of inherited syndromes.•Recent advances in molecular genetics have allowed the identification of multiple genes relevant to vascular malformations.•We reviewed of each of the representative syndromes of vascular malformations associated with PIK3CA and RAS cascades.•Even more so as new treatments become available, the accurate diagnosis of these rare disorders is vital.