Haemangiopericytoma

Definition

  • Obsolete term for a tumour with branching staghorn vessels
  • WHO now places almost all cases within solitary fibrous tumour (SFT)
  • Intermediate, rarely metastasising, with a malignant subset

Epidemiology

  • Adults, most often middle aged, with no strong sex predilection
  • Pleura, meninges, deep thigh, pelvis, retroperitoneum and head and neck
  • Primary bone involvement is rare
  • Meningeal haemangiopericytoma is now termed meningeal SFT

Pathology

Haemangiopericytoma, histology of solitary fibrous tumour, the current term for haemangiopericytoma
Histology of solitary fibrous tumour, the current term for haemangiopericytoma. Image by Daigeler A, Lehnhardt M, Langer S, Steinstraesser L, Steinau HU, Mentzel T, Wikimedia Commons, CC BY 2.5.
  • Patternless ovoid to spindle cells in variably collagenous stroma
  • Thin walled, branching, dilated staghorn vessels
  • NAB2 to STAT6 fusion on chromosome 12
  • Strong nuclear STAT6 staining is the diagnostic marker
  • CD34 usually positive
  • Haemangiopericytoma-like vessels also occur in synovial sarcoma and mesenchymal chondrosarcoma

Clinical Features

  • Slowly enlarging, usually painless deep mass
  • Pressure symptoms from large pelvic or retroperitoneal tumours
  • Doege-Potter syndrome, paraneoplastic hypoglycaemia from tumour IGF-2 secretion in large tumours
  • Bone lesions present with pain or pathological fracture

Investigations

CT of a solitary fibrous tumour of the pleura
CT of a solitary fibrous tumour of the pleura. Image by Stockholm, Wikimedia Commons, CC BY-SA 4.0.
  • MRI shows a well circumscribed, heterogeneous, avidly enhancing mass with flow voids
  • CT angiography shows hypervascularity
  • Core biopsy at a sarcoma centre with STAT6 immunohistochemistry
  • Staging CT chest, with liver and bone other metastatic sites

Classification

  • Histology alone does not reliably predict behaviour
  • Risk models combine age, tumour size, mitotic rate and necrosis
  • Tumours graded low, intermediate or high risk for metastasis

Management

  • Wide surgical excision is the primary treatment
  • Preoperative embolisation reduces blood loss in vascular tumours
  • Radiotherapy for close or positive margins and unresectable disease
  • Conventional chemotherapy has modest activity
  • Pazopanib, or temozolomide with bevacizumab, for advanced disease
  • Hypoglycaemia resolves after complete resection

Prognosis

  • Most behave indolently after complete excision
  • Recurrence and metastasis may occur beyond ten years
  • Long term follow up, particularly for intermediate and high risk tumours

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.