Hemangiopericytoma in Adult
HAP occurs mainly in adults; children are rarely affected. Both sexes are affected equally. Because of the asymptomatic nature of HAP, the diagnosis may be delayed by months or even years, particularly for low-grade and slow-growing lesions. More aggressive forms of HAP exist as well. Morbidity and mortality are attributed to locally invasive disease and hematogenous metastases to the lungs (most common) or the intra-abdominal or retroperitoneal region.
Pediatric Patient Considerations:
HAP is rare in children, accounting for less than 10% all cases. A rare form of infantile HAP (in children less than 1 year old) is considered congenital.
D48.1 – Neoplasm of uncertain behavior of connective and other soft tissue
134335004 – Hemangiopericytoma
Differential Diagnosis & Pitfalls
- Angiosarcoma – any tumor of vessel origin; liver angiosarcoma is fatal and associated with vinyl chloride exposure
- Chondrosarcoma, mesenchymal type – rarely associated with metastases
- Fibrous histiocytoma – general category for any soft tissue sarcoma not otherwise specified
- Lymphangiosarcoma – arises in limbs with chronic primary or secondary lymphedema (upper > lower)
- Solitary fibrous tumor – considered a benign neoplasm
- Synovial sarcoma – occurs near joints
- Vascular lesions (eg, vascular malformations or aneurysms) – audible bruits may sometimes be present due to the high vascularity of HAP