title: Head and neck hemangiopericytomas: diagnostic contradictions.
abstract: OBJECTIVE
  To identify misdiagnostic points of hemangiopericytomas (HPs) of the head and neck.
  
  
  METHODS
  We reviewed our clinical records from 2000 to 2007 retrospectively and identified 5 patients with HP of the head and neck. The records of each patient with head and neck HP were evaluated for age, sex, location of primary, clinical course, treatment, and tumor embolization (if performed). Pathologic slides of all patients were reviewed to identify histologic features and correlation with the clinical course and outcome for each lesion.
  
  
  RESULTS
  Five patients with HP that arose from head and neck sites were identified. Five patients included 3 women and 2 men aged 9 to 52 years, with an average of 33.2 years. Each lesion of the patients derived from different parts of the head and neck. The most common complaints were painless mass (3 of 5) and nasal airway obstruction (3 of 5). Magnetic resonance imaging of the 3 patients reflected hyperintense on T2-weighted imaging and hypointense on T1-weighted imaging with diffuse enhancement after intravenous administration of gadolinium. Angiography was performed to all these 3 patients, and only 1 patient with cranial HP involvement did not show significant vascularity. Two patients had preoperative histopathologic results. All patients were operated on with appropriate approach. Pathologic slides of all patients were investigated and graded according to the tumor diameter, cellularity, mitotic rate, and necrosis.
  
  
  CONCLUSIONS
  Differential diagnosis of clinical features and radiologic and pathologic aspects must be managed more carefully. Diagnostic way of these tumors has different pitfalls for the clinician.
authors.affiliation: Department of Otorhinolaryngology, Istanbul Training and Research Hospital, Istanbul, Turkey. drengin@hotmail.com
authors.forename: Engin
authors.initials: E
authors.lastname: Acioğlu
authors.forename: Harun
authors.initials: H
authors.lastname: Cansiz
authors.forename: Hasan
authors.initials: H
authors.lastname: Mercan
authors.forename: Sergülen
authors.initials: S
authors.lastname: Dervişoğlu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001706:Biopsy; D002648:Child; D003287:Contrast Media; D003937:Diagnosis, Differential; D004621:Embolization, Therapeutic; D005260:Female; D005500:Follow-Up Studies; D005682:Gadolinium; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000601:surgery; D018324:Hemangioma, Capillary / Q000175:diagnosis; D006393:Hemangiopericytoma / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008579:Meningioma / Q000175:diagnosis; D008875:Middle Aged; D015508:Nasal Obstruction / Q000175:diagnosis; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003287:Contrast Media; D005682:Gadolinium