Advances in vascular anomalies: refining classification in the molecular era

The classification and understanding of vascular anomalies have significantly evolved since the initial framework by Mulliken and Glowacki, distinguishing between vascular tumours and malformations. Recent advancements in molecular diagnostics have enhanced the accuracy of identifying and managing these complex lesions. This review provides an updated analysis of select vascular anomalies, focusing on Kaposiform hemangioendothelioma (KHE), Kaposiform lymphangiomatosis (KLA), and intramuscular fast-flow vascular anomalies. It highlights the similarities and differences between these lesions, their histopathological features, and molecular underpinnings, including key genetic mutations in the RAS/PI3K/mTOR signalling pathways. Moreover, the role of PIK3CA mutations in vascular overgrowth syndromes is explored, alongside emerging targeted therapies, such as PI3K and MEK inhibitors, that promise improved outcomes for patients with these challenging conditions. The integration of histology, molecular diagnostics, and multidisciplinary care remains critical for the accurate diagnosis and optimal treatment of vascular anomalies in the era of precision medicine.