title: Hemangiopericytoma of the nose: a case for both internal and external localization.
abstract: BACKGROUND
  Nasal and paranasal cavities are sites of predilection for hemangiopericytoma (HPC), a rare vascular tumor described for the first time in 1942. Because of their characteristics, i.e. clinical presentation, age distribution and biological behavior, nasal HPCs are frequently reported as "hemangioperycitoma-like intranasal tumors" although such a distinction from other HPCs is debated.
  
  
  RESULTS
  out of nearly 64,000 autopsies and 336,000 surgical and endoscopic biopsies performed at the University of Trieste over 30 years, only three cases of HPC have been found, two of them affecting the external nose; for both there was a good agreement between histology--supported by immunohistochemistry and flow cytometry--and biological behavior.
  
  
  CONCLUSIONS
  On the basis of the sparse literature on skin HPC and of our two cases, we suggest that not only the internal, but also the external nose should be considered a predilection site for HPC.
authors.affiliation: Department of Pathology, University of Trieste, Italy. melato@univ.trieste.it
authors.forename: M
authors.initials: M
authors.lastname: Melato
authors.forename: N
authors.initials: N
authors.lastname: Gorji
authors.forename: N
authors.initials: N
authors.lastname: Jonjic
mesh_terms: D000328:Adult; D006393:Hemangiopericytoma / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D009666:Nose