Vertebral hemangiomas: common lesions with still many unknown aspects

Histologically VHs are not considered vascular neoplasms, but rather hamartomas or malformation of the microcirculation. Basing on the predominant type of vascular channel they are classified in: capillary, cavernous, arterio-venous and venous malformations. Most of spinal epidural hemangiomas belongs to the cavernous type (1). Numerous terms have been introduced and different classification systems. Unfortunately, none of these has been accepted due to the lack of accepted histological criteria and limited correlation with clinical outcome. Vascular tumours of bone originate from endothelial cells resulting in variable expression of endothelial markers, but none of these markers is useful to discriminate between benign and malignant lesions. Verbeke and Bovée (2) proposed the classification of vascular tumours of bone according to the WHO classification scheme for soft tissue tumours dividing entities into benign, intermediate and malignant category.