title: Giant cell tumours of the mobile spine: characteristic imaging features and differential diagnosis.
abstract: OBJECTIVE
  The aim of this study was to investigate the characteristic imaging features of giant cell tumours (GCTs) of the mobile spine.
  
  
  METHODS
  Thirty pathologically proven GCTs of the mobile spine were reviewed. X-ray (n = 18), computed tomography (CT) (n = 24) and magnetic resonance (MR) (n = 21) images were retrospectively evaluated.
  
  
  RESULTS
  Five tumours were located in the cervical spine, 15 tumours were located in the thoracic spine and 10 tumours in the lumbar spine. The characteristic X-ray findings included an osteolytic and expansile lesion with a "soap bubble" or purely lytic appearance. Cortical destruction was commonly seen. Margin sclerosis was seen in two lesions. No mineralised tumour matrix or periosteal reaction appeared. The CT findings were similar but outlined the cortical alterations in a more accurate way. The characteristic MR findings included a well-defined and expansile mass with heterogeneous low-to-iso signal intensity on T2-weighted images. Cystic areas were commonly seen in 17 cases. Five cases presented fluid-fluid levels, suggesting the development of aneurysmal bone cyst. The solid portions of the tumours were enhanced with a very heterogeneous signal pattern reflecting high blood supply after contrast-enhanced scan. Tumour involvement in the epidural space occurred in 12 cases, causing spinal cord and/or nerve root compression. Involvement of intervertebral discs and/or adjacent vertebrae appeared in two cases.
  
  
  CONCLUSIONS
  Although rare, GCT can occur in the mobile spine as a kind of benign but locally aggressive tumour. Radiologists should be familiar with its characteristic imaging features in order to make a correct diagnosis and to help preoperative evaluations.
authors: Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197, Ruijin 2nd Road, Shanghai, 200025, China, smjsh@hotmail.com.
authors: Ming-Jue
authors: MJ
authors: Si
authors: Chen-Guang
authors: CG
authors: Wang
authors: Cheng-Sheng
authors: CS
authors: Wang
authors: Lian-Jun
authors: LJ
authors: Du
authors: Xiao-Yi
authors: XY
authors: Ding
authors: Wei-Bin
authors: WB
authors: Zhang
authors: Yong
authors: Y
authors: Lu
authors: Jin-Yan
authors: JY
authors: Zu
mesh_terms: D000293:Adolescent; D000328:Adult; D002574:Cervical Vertebrae; D003937:Diagnosis, Differential; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013125:Spinal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D013904:Thoracic Vertebrae; D014057:Tomography, X-Ray Computed