Chapter 73
Nasopharyngeal Hemangiopericytoma
Epidemiology
Hemangiopericytomas are unusual vascular tumors that occur mainly in adults. They represent 1% of all vasoformative tumors, most of which occur in the lower extremity, retroperitoneum, and pelvis. Approximately 15 to 20% occur in the head and neck region. They may be found in the sinonasal area, orbit, lacrimal sac, or jugular foramen. About 50% of cases are malignant, and distant metastasis, although rare, may occur, especially to the lungs. Differentiation between malignant and benign tumors may be a difficult pathological task and clinical correlation is required. Electron microscopy and immunohistochemical techniques may be necessary to differentiate hemangiopericytomas from other sarcomatous tumors.
Clinical Findings
Patients usually present with a history of epistaxis, nasal obstruction, or discharge. Facial pain may be related to associated paranasal sinusitis secondary to tumor obstructing the drainage pathways.
Pathology