Meningeal Hemangiopericytoma

Synonyms: Angioblastic Meningiomas

Definition

Highly vascular and cellular tumor of the meninges, WHO grade II or III, with a tendency to recurrence and late metastasis, and similar histologic appearance to hemangiopericytoma outside the CNS.

Clinical Features

Mainly adults
No predilection for women (unlike meningioma)
Extracranial metastasis:
- usually late complication
- most often:
  - lungs
  - bones
  - liver
- also retroperitoneal organs, such as kidney and pancreas1

Gross Pathology

Strongly favor intracranial compartment

Histopathology

Cytogenesis contentious
Dura-based tumor long regarded as ‘angioblastic’ variant of meningioma
Morphologically indistinguishable from hemangiopericytomas in somatic soft tissues1–3 (Fig. 1
Fig. 1: Meningeal hemangiopericytoma. Long regarded as a form of ‘angioblastic’ meningioma, this lesion is now widely accepted as the homolog of its extraneural soft tissue counterpart.
)
Often:
- a network of ‘reticulin’ investing individual tumor cells
  - appears to represent basal lamina material ultrastructurally1,3 (Fig. 2
    Fig. 2: Meningeal hemangiopericytoma. Unlike the cytoplasmic processes of meningothelial tumor cells, those of the hemangiopericytoma's constituent neoplastic elements are separated by basal lamina material demonstrable on ultrastructural examination. (×11,360)
    )
Ultrastructurally:
- cytoplasmic processes elaborated by its constituent cells are joined by rudimentary junctions
  - not bound by well-developed desmosomes nor intertwined in complex fashion

Special Stains and Immunohistochemistry

Do not express EMA1,4,5
May label for CD34:
- usually weak and patchy:
  - unlike diffuse and often strong cytoplasmic reactivity typical of solitary fibrous tumors 5,6

Differential Diagnosis

Select up to 2 differential diagnoses to compare with Meningeal Hemangiopericytoma

Meningioma showing Potentially Misleading Pericytomatous Growth Patterns

Distinction usually straightforward
Psammomatous calcospherites, tumor cells concentrically arrayed in tight whorl formations, and intranuclear pseudoinclusions not seen in hemangiopericytomas

Mesenchymal Chondrosarcomas of Dural Origin

Routinely harbor anaplastic small cell elements in pericytomatous architectural array
Meningeal hemangiopericytoma lacks chondroid components

Management

Resection
Postoperative radiotherapy

Prognosis

Regrowth at primary site despite seemingly complete initial resection:
- typical
- may take years to become clinically apparent
Death common due to intracranial tumor progression:
- often after a protracted course with repeated local recurrence1–3
Poor prognostic factors may be:
- foci of necrosis 1,2

References

1 Mena H, Ribas JL, Pezeshkpour GH, Cowan DN, Parisi JE. Hemangiopericytoma of the central nervous system. A review of 94 cases. Hum Pathol. 1991;22:84–91.

2 Guthrie BL, Ebersold MJ, Scheithauer BW, Shaw EG. Meningeal hemangiopericytoma. Histopathological features, treatment, and long-term follow-up of 44 cases. Neurosurgery. 1989;25:514–522.

3 Jääskeläinen J, Louis DN, Paulus W, Haltia MJ. Haemangiopericytoma. Kleihues P, Cavanee WK editor. World Health Organization classification of tumours. Pathology and genetics-tumours of the nervous system. Lyon: IARC Press; 2000.

4 Winek RR, Scheithauer BW, Wick MR. Meningioma, meningeal hemangiopericytoma (angioblastic meningioma), peripheral hemangiopericytoma, and acoustic schwannoma. A comparative immunohistochemical study. Am J Surg Pathol. 1989;13:251–261.

5 Perry A, Scheithauer BW, Nascimento AG. The immunophenotypic spectrum of meningeal hemangioperiocytoma. A comparison with fibrous meningioma and solitary fibrous tumor of meninges. Am J Surg Pathol. 1997;21:1354–1360.

6 Tihan T, Viglione M, Rosenblum MK, Olivi A, Burger PC. Solitary fibrous tumors in the central nervous system. A clinicopathologic review of 18 cases and comparison to meningeal hemangiopericytomas. Arch Pathol Lab Med 127: 432-439.

Last updated: 16 Feb 2006