title: Recurrence in giant cell tumour of bone: imaging features and risk factors.
abstract: OBJECTIVE
  This study was done to investigate X-ray, computed tomography (CT) and magnetic resonance (MR) imaging features of recurrence in giant cell tumour of bone (GCTB) and to evaluate risk factors.
  
  
  METHODS
  Medical records and imaging data were reviewed for 55 cases of recurrent GCTB. All images were reviewed retrospectively and independently by two radiologists experienced in skeletal musculature. The common radiological findings; factors related to tumour recurrence such as gender, age, location; pathological fracture, Campanacci grading and surgical procedure were analysed by nonparametric test (Mann-Whitney U test for two independent samples test and Kruskal-Wallis H test for multiple independent samples test). p values <0.05 were considered to indicate a statistically significant difference.
  
  
  RESULTS
  The imaging features of recurrent GCTB were as follows: osteolytic destruction or bone resorption of graft bone or around the polymethylmethacrylate (PMMA), soft tissue mass formation and expansile change. Tumour parenchyma showed markedly heterogeneous enhancement, except for necrotic cystic cavities, on contrast-enhanced MR images. Wide resection had a smaller (p=0.031) risk of local recurrence than did intralesional curettage. There was no statistical significance in gender, age, location, pathological fracture and Campanacci staging (p>0.05).
  
  
  CONCLUSIONS
  The risk of recurrence in GCTB was influenced by the type of surgery and adjuvants. Bone transformaresorption, soft tissue mass formation and aggravated expansile change are reliable signs of recurrence on imaging.
authors.affiliation: Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Cheng-Sheng
authors.initials: CS
authors.lastname: Wang
authors.forename: Jiang-Hua
authors.initials: JH
authors.lastname: Lou
authors.forename: Jin-Sheng
authors.initials: JS
authors.lastname: Liao
authors.forename: Xiao-Yi
authors.initials: XY
authors.lastname: Ding
authors.forename: Lian-Jun
authors.initials: LJ
authors.lastname: Du
authors.forename: Yong
authors.initials: Y
authors.lastname: Lu
authors.forename: Ling
authors.initials: L
authors.lastname: Yan
authors.forename: Ke-Min
authors.initials: KM
authors.lastname: Chen
mesh_terms: D000328:Adult; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D016009:Chi-Square Distribution; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000473:pathology*; D009367:Neoplasm Staging; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*