Hemangiopericytoma

Deborah R. Shatzkes, MD

Key Facts

Terminology

Hemangiopericytoma (HPC)
Uncommon, slow-growing vascular neoplasm of varying malignancy

Imaging

Most HPCs occur in lower extremities, pelvis
15% occur in head and neck
- Intracranial/meningeal: Parasellar & paraclival
- Orbit, cervical soft tissues, sinonasal cavity
CT findings
- Well circumscribed, lobular, avidly enhancing; more invasive behavior if high grade (CECT)
- May see bone erosion or remodeling (bone CT)
MR findings
- Intermediate T1, high T2 signal
- Vascular flow voids common
- Prominent enhancement, typically uniform

Top Differential Diagnoses

Skull base meningioma
Skull base metastasis
Skull base trigeminal schwannoma
Clivus chordoma
Orbital cavernous hemangioma
Sinonasal angiomatous polyp

Pathology

50% malignant, typically low grade

Clinical Issues

Resection is treatment of choice ± XRT
Local recurrence ≤ 50%; 30% metastases < 10 years
HPC mimics many more common tumors
Consider HPC if avidly enhancing, well-circumscribed mass

(Left) Axial CECT shows skull base HPC with bone destruction and extension into middle fossa

and masticator space

. Absence of hyperostosis is clue that this is not meningioma, though distinction from other destructive extraaxial masses is difficult. (Right) Coronal T1WI C+ FS MR reveals parasellar HPC with intrasellar