Vascular Anomalies: Nomenclature and Diagnosis

Before the development of the International Society for the Study of Vascular Anomalies (ISSVA) classification system in 1996, nomenclature used to describe vascular lesions was inconsistent and imprecise. This since widely adopted system stratifies vascular anomalies into vascular malformations and tumors. Vascular tumors involve abnormal proliferation of vascular cells and are further classified as benign, locally aggressive/borderline, or malignant. Vascular malformations are lesions of defective vascular morphogenesis with quiescent endothelium and are named according to their vessel composition, and subdivided into simple; combined, of major named vessels; and syndrome-associated malformations. The updated 2018 ISSVA criteria are referenced in this review.