title: Sinonasal undifferentiated carcinoma: CT and MR imaging of an uncommon neoplasm of the nasal cavity.
abstract: OBJECTIVE
  To determine the computed tomographic (CT) and magnetic resonance (MR) imaging appearance of sinonasal undifferentiated carcinoma.
  
  
  METHODS
  Findings from 11 patients with histopathologically proved sinonasal undifferentiated carcinoma were retrospectively reviewed. All 11 patients had undergone CT, and six of them had undergone MR imaging.
  
  
  RESULTS
  The tumors usually were large (larger than 4 cm in maximum dimension in eight patients), had poorly defined margins, and arose within the ethmoid sinuses and superior nasal cavity. The aggressive nature of the tumor was demonstrated by bone destruction (n = 10) and by invasion of adjacent structures, including paranasal sinuses (n = 10), anterior fossa (n = 7), orbits (n = 4), pterygopalatine fossa (n = 2), parapharyngeal space (n = 1), and cavernous sinus (n = 1). On contrast material-enhanced CT scans, all tumors were enhanced to varying degrees. They tended to be noncalcified (n = 10) and often caused sinus obstruction (n = 10). MR signal intensity of the lesions was isointense to muscle on T1-weighted images in all six patients and iso- to hyperintense on T2-weighted images in five patients. Heterogeneous enhancement of tumors was seen on gadolinium-enhanced images.
  
  
  CONCLUSIONS
  Sinonasal undifferentiated carcinoma cannot be distinguished from other tumors of this region (with the possible exception of melanoma) on the basis of imaging features.
authors.affiliation: Department of Radiology, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Phillips
authors.forename: S F
authors.initials: SF
authors.lastname: Futterer
authors.forename: M H
authors.initials: MH
authors.lastname: Lipper
authors.forename: P A
authors.initials: PA
authors.lastname: Levine
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D003937:Diagnosis, Differential; D005005:Ethmoid Sinus; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity; D009361:Neoplasm Invasiveness; D009669:Nose Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D010255:Paranasal Sinus Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed