Update on classification and diagnosis of vascular malformations.

PURPOSE OF REVIEW: This review provides an update of the classification in the classification of vascular anomalies since April 2014 at the International Society for the Study of Vascular Anomalies meeting in Melbourne, Australia.

RECENT FINDINGS: The reader will become familiar with how to diagnose the major vascular malformations, including capillary, venous, arteriovenous, and lymphatic and combinations thereof. In addition, vascular malformation syndromes, including those with overgrowth, will be clarified.

SUMMARY: Vascular malformations are common. Capillary malformations are now better understood through an updated classification. Verrucous hemangioma is truly a venulocapillary malformation that extends into the subcutis. PIK3Ca-Related Overgrowth Syndromes encompass Klippel-Trenaunay, Congenital Lipomatous Asymmetric Overgrowth of the Trunk with Lymphatic, Capillary, Venous, and Combined-Type Vascular Malformations, Epidermal Nevi, Scoliosis/Skeletal and Spinal Anomalies, Megalencephaly-Capillary Malformation-Polymicrogyria Syndrome (M-CAP), fibroadipose hyperplasia, and macrodactyly. Yet another syndrome should be highlighted: Capillary Malformation of the Lower Lip, Lymphatic Malformation of the Face and Neck, Asymmetry and Partial/Generalized Overgrowth. Knowledge of the genetic basis of vascular malformations will lead to future treatments.