[Interpretation of updated guidelines on diagnosis of hemangiomas and vascular anomalies]

The International Society for the Study of Vascular Anomalies (ISSVA) classification is an internationally accepted framework for the diagnosis and communication of vascular tumors and vascular malformations. Since the tumor-versus-malformation dichotomy was established in 1996, the classification underwent major revisions in 2014 and 2018. In June 2025, the ISSVA Classification Group published an updated classification in the Journal of Vascular Anomalies and positioned it as a continuously updated "living document", representing the most substantial revision to date. Key updates include: at the top level, the new category "potentially unique vascular anomaly" replaces the former "provisionally unclassified vascular anomalies"; a two-tier structure comprising a landing page and a full classification table is introduced, together with an independent glossary; for vascular malformations, vessel type (simple versus combined) is no longer the primary organizing criterion, and the classification is now organized by flow velocity (fast-flow versus slow-flow) together with developmental anomalies of named vessels; and molecular genetic information has been systematically incorporated. Using the 2018 version as a reference, this article reviews the key updates of the 2025 version and interprets them in the context of advances in molecular genetics, targeted therapy, and the practice of vascular anomaly diagnosis and treatment in China, aiming to provide a reference for standardized diagnosis, multidisciplinary communication, and individualized treatment decisions.