Vascular Tumors of Bone: The Evolvement of a Classification Based on Molecular Developments.

The classification of vascular tumors of bone has been under debate over time. Vascular tumors in bone are rare, display highly overlapping morphology, and, therefore, are considered difficult by pathologists. Compared with their soft tissue counterparts, they are more often multifocal and sometimes behave more aggressively. Over the past decade, with the advent of next-generation sequencing, recurrent molecular alterations have been found in some of the entities. The integration of morphology and molecular changes has led to a better characterization of these separate entities.