Haemangioendothelioma

Definition

  • Vascular tumours between haemangioma and angiosarcoma in behaviour
  • Epithelioid haemangioendothelioma (EHE) is the main orthopaedic variant
  • WHO classes EHE as fully malignant, low to intermediate grade

Epidemiology

  • Rare, most often in young and middle aged adults
  • Arises in soft tissue, bone, liver and lung
  • Bone EHE favours lower limb long bones, then pelvis, spine and ribs

Pathology

Histology of epithelioid haemangioendothelioma
Histology of epithelioid haemangioendothelioma. Image by Yale Rosen from USA, Wikimedia Commons, CC BY-SA 2.0.
  • Cords and nests of epithelioid endothelial cells in myxohyaline or chondroid-like stroma
  • Intracytoplasmic vacuoles, sometimes containing red cells (“blister cells”)
  • CD31, ERG and FLI1 positive
  • Keratin positivity risks misdiagnosis as metastatic carcinoma
  • Most carry a WWTR1 to CAMTA1 fusion, with nuclear CAMTA1 staining
  • A minority carry a YAP1 to TFE3 fusion and look more vasoformative

Clinical Features

  • Localised pain, with or without swelling
  • Pathological fracture, or an incidental finding
  • Multifocal bone disease is common, often clustered in one limb

Investigations

  • Lytic lesions, sometimes expansile, with little periosteal reaction
  • Multiple lesions in one limb suggest a vascular tumour
  • MRI shows low T1 and high T2 signal with enhancement
  • Whole body staging with CT chest and abdomen or PET
  • Biopsy confirms the diagnosis

Differential Diagnosis

  • Metastatic carcinoma and myeloma
  • Epithelioid haemangioma
  • Epithelioid angiosarcoma
  • Chondroid tumours, owing to the stroma

Management

  • Wide or marginal resection for solitary resectable lesions
  • Curettage carries a higher recurrence risk
  • Radiotherapy for unresectable, multifocal or spinal disease and close margins
  • Multifocal or visceral disease under a sarcoma MDT, with surveillance for indolent cases
  • Antiangiogenic agents or trametinib for progressive disease

Prognosis

  • Unpredictable, with a prolonged course in many bone cases
  • Pleural, extensive lung or liver involvement predicts worse outcome
  • Better prognosis than angiosarcoma

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