title: Usefulness of increased 18F-FDG uptake for detecting local recurrence in patients with extremity osteosarcoma treated with surgical resection and endoprosthetic replacement.
abstract: OBJECTIVE
  To investigate the changes of increased F-18 fluorodeoxyglucose ((18)F-FDG) uptake around the prosthesis and its ability to differentiate local recurrence from postsurgical change after endoprosthetic replacement in extremity osteosarcoma.
  
  
  METHODS
  A total of 355 positron emission tomography (PET)/computed tomography (CT) scans in 109 extremity osteosarcoma patients were retrospectively analyzed. All patients were followed up with (18)F-FDG PET/CT for more than 3 years after tumor resection. For semiquantitative assessment, we drew a volume of interest around the entire prosthesis of the extremity and measured the maximum standardized uptake value (SUV max). Independent samples t test was used to compare SUV max at each follow-up time. SUV max at 3 months (SUV1) and SUV max at the time of local recurrence in patients with recurrence or at the last follow-up in others (SUV2) were compared using the Mann-Whitney test. Diagnostic performances of PET parameters were assessed using ROC curve analyses.
  
  
  RESULTS
  Nine patients (8 %) showed a local recurrence. Mean SUV max at 3, 12, 24, and 36 months was 3.1 ± 1.5, 3.8 ± 1.9, 3.6 ± 1.9, and 3.7 ± 1.5 respectively. In ROC curve analysis, the combination of SUV2 >4.6 and ΔSUV >75.0 was a more useful parameter for predicting local recurrence than SUV2 or ΔSUV alone. The sensitivity, specificity, and accuracy for identifying local recurrence were 89, 76, 77 % for SUV2; 78, 81, 81 % for ΔSUV; and 78, 94, 93 % for the combined criterion respectively.
  
  
  CONCLUSIONS
  The combination of SUV2 and ΔSUV was more useful than the SUV2 or ΔSUV used alone for the prediction of local recurrence.
authors.affiliation: Department of Nuclear Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences (KIRAMS), 75 Nowongil, Nowon Gu, Seoul, 139-706, South Korea.
authors.forename: Kyoung Jin
authors.initials: KJ
authors.lastname: Chang
authors.forename: Chang-Bae
authors.initials: CB
authors.lastname: Kong
authors.forename: Wan Hyeong
authors.initials: WH
authors.lastname: Cho
authors.forename: Dae-Geun
authors.initials: DG
authors.lastname: Jeon
authors.forename: Soo-Yong
authors.initials: SY
authors.lastname: Lee
authors.forename: Ilhan
authors.initials: I
authors.lastname: Lim
authors.forename: Sang Moo
authors.initials: SM
authors.lastname: Lim
mesh_terms: D000293:Adolescent; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D005121:Extremities / Q000000981:diagnostic imaging / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D064847:Multimodal Imaging / Q000379:methods; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D012516:Osteosarcoma / Q000175:diagnosis* / Q000601:surgery*; D049268:Positron-Emission Tomography; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D012372:ROC Curve; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18