Hemangiopericytoma (Central Nervous System)

Hemangiopericytomas are hyperattenuating extra-axial lesions with dural attachments that may mimic meningiomas. Unlike meningiomas, however, they do not demonstrate calcifications or hyperostosis and often have a heterogeneous enhancement. Meningiomas also demonstrate broad-based dural attachment and are typically round. Hemangiopericytomas, on the other hand, have narrow bases of attachment and are usually lobulated.

Unlike meningiomas, which displace vessels, hemangiopericytomas demonstrate internal flow voids. The angiographic pattern is also different. As opposed to the spoke-wheel pattern of vessels, the vessels in hemangiopericytomas are irregularly arranged.

Differential considerations include:

• Meningioma
• Dural metastases
• Lymphoma
• Neurosarcoidosis
• Gliosarcoma

More recently, the concept of hemangiopericytoma as a distinct entity has come into question, with the majority of these tumors now classified as solitary fibrous tumors.

References

• Gengler C, Guillou L. Solitary fibrous tumour and haemangiopericytoma: evolution of a concept. Histopathology. 2006 Jan;48(1):63-74.
• Salzman KL. Hemangiopericytoma. StatDx. Updated 2008-06-02.