Hemangiopericytoma is a term formerly used to describe a continuum of mesenchymal tumors with elevated cellularity found throughout the body in soft tissue and bone. After many years of controversy, hemangiopericytomas have been shown to not only share histological features similar to solitary fibrous tumors but also a similar genetic alteration; i.e. a genomic inversion of 12q13 locus resulting in fusion of NAB2 and STAT6 genes, the latter expressed and able to be assessed using immunohistochemistry techniques 4.
As a result, systemically the term "hemangiopericytoma" is/should no longer be routinely used.
In the central nervous system, as of the 5th edition (2021) of the WHO classification of CNS tumors, the term hemangiopericytoma has been retired, and is now included as a continuum of solitary fibrous tumor of the dura 5.
History and etymology
The term was first used by the American pathologists Arthur Purdy Stout and Margaret Ransone Murray in 1942 to describe a soft tissue tumor presumably of pericytic origin, with a monomorphic population of compact polygonal or fusiform cells and a branching stromal vascular pattern with a "staghorn" form 3,4.