title: Synovial sarcomas of the head and neck: CT and MR imaging findings of eight patients.
abstract: OBJECTIVE
  Synovial sarcomas are soft-tissue tumors that rarely occur in the head and neck. The purpose of this study was to evaluate their CT and MR imaging appearance and to show that they may have a surprisingly benign imaging appearance.
  
  
  METHODS
  Eight patients with histologically proved synovial sarcoma underwent CT; additionally, MR imaging examinations were performed in five of the eight cases. Attenuation and signal intensity on CT scans and MR images, respectively, were studied by two radiologists. They analyzed the location, size, margins, homogeneity, presence of adenopathies and infiltrative signs, and enhancement after injection of contrast medium.
  
  
  RESULTS
  Four tumors were located in the hypopharynx, two arose from the infratemporal fossa, one arose from the maxillary sinus, and one arose from the faucial tonsil. Tumor sizes ranged from 27 to 70 mm. On CT scans and MR images, six lesions were homogeneous and well defined, with smooth margins. The remaining tumors were heterogeneous. In two cases, adjacent tissues were invaded. Calcifications were observed in one case and adenopathy in two cases. In three cases, the lesions were isointense on T1-weighted MR images and hypointense on T2-weighted MR images, and in the other two cases in which MR imaging was performed, the lesions were both isointense and hypointense on both T1- and T2-weighted images. Only the two local recurrent lesions were multilocular.
  
  
  CONCLUSIONS
  Synovial sarcomas are aggressive sarcomas that may appear "benign" in some cases. In a young man, a synovial sarcoma may be suspected when a well-demarcated, homogeneous lesion is found in the head and neck.
authors.affiliation: Department of Radiology, Institut Gustave-Roussy, F-94805 Villejuif Cedex, France.
authors.forename: A S
authors.initials: AS
authors.lastname: Rangheard
authors.forename: D
authors.initials: D
authors.lastname: Vanel
authors.forename: J
authors.initials: J
authors.lastname: Viala
authors.forename: G
authors.initials: G
authors.lastname: Schwaab
authors.forename: O
authors.initials: O
authors.lastname: Casiraghi
authors.forename: R
authors.initials: R
authors.lastname: Sigal
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002114:Calcinosis / Q000175:diagnosis; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis*; D006801:Humans; D008206:Lymphatic Diseases / Q000175:diagnosis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D013584:Sarcoma, Synovial / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed