title: CT imaging of primary pleuropulmonary synovial sarcoma.
abstract: OBJECTIVE
  To evaluate the computed tomography (CT) imaging findings of primary pleuropulmonary synovial sarcoma.
  
  
  METHODS
  Five cases of synovial sarcoma confirmed by histopathology and cytogenetic study were retrospectively analysed. All patients had undergone chest radiography and unenhanced and contrast-enhanced CT examinations, and three had also undergone multiphase CT enhancement examinations. Image characteristics, including shape, size, margin, and attenuation of each lesion before and after contrast enhancement, were analysed.
  
  
  RESULTS
  The chest radiographs of the five patients showed well-defined or partly well-defined masses, which were homogeneous and without associated calcification or lymphadenopathy. Pneumothorax was present in one patient. The unenhanced CT images showed well-defined, heterogeneous masses with patchy low density in all five patients. The contrast-enhanced CT images showed heterogeneous enhancement in all cases, three of which demonstrated cystic and necrotic areas. The tumour showed no prolonged or delayed enhancement in three cases using multiphase CT. There were small pleural effusions in four cases. No calcification was observed in any of the cases. There was no evidence of hilar or mediastinal lymphadenopathy.
  
  
  CONCLUSIONS
  In these five patients, primary pleuropulmonary synovial sarcoma presented as a well-defined mass with patchy low density and heterogeneous enhancement, with no evidence of regional lymphadenopathy. It should be included in the differential diagnosis of regional tumours.
authors.affiliation: Department of Radiology, State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-sen University, PR China.
authors.forename: W-D
authors.initials: WD
authors.lastname: Zhang
authors.forename: Y-B
authors.initials: YB
authors.lastname: Guan
authors.forename: Y-F
authors.initials: YF
authors.lastname: Chen
authors.forename: C-X
authors.initials: CX
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010997:Pleural Neoplasms / Q000000981:diagnostic imaging* / Q000648:ultrastructure; D011856:Radiographic Image Enhancement / Q000379:methods; D013902:Radiography, Thoracic / Q000379:methods*; D012189:Retrospective Studies; D013584:Sarcoma, Synovial / Q000000981:diagnostic imaging* / Q000648:ultrastructure; D036542:Tomography, Spiral Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide