title: Incremental value of fusion imaging with integrated PET-CT in oncology.
abstract: OBJECTIVE
  The purpose of this study was to assess the incremental value of integrated F-18 FDG PET-CT imaging compared with either alone for evaluation of patients with body malignancies.
  
  
  METHODS
  Images from 173 consecutive patients with body malignancies referred for integrated PET-CT imaging were reviewed. A CT with contrast performed within 2 months of PET-CT was available for 74 patients.
  
  
  RESULTS
  There was agreement between the transmission CT (TrCT) and PET interpreted separately in 65% (112 of 173) of patients. Interpretation of integrated PET-CT had an incremental diagnostic value in 17.9% (31 of 173) of the total patient population. Data was analyzed further excluding patients for whom further analysis was not relevant: 1) 20% (34 of 173) of patients with normal TrCT and PET and 2) 11% (19 of 173) of patients with disseminated metastases (too numerous to count) on both TrCT and PET. Among the 120 other patients, PET interpreted alone was positive in 195 body regions and CT-positive in 178 body regions with agreement for all regions in 49% (59 of 120) of patients and discordance or equivocal lesions in 51% (61 of 120) of patients. Integrated PET-CT had an incremental diagnostic value in 27% (31 of 120) of patients. Contrasted CT scan demonstrated hepatic lesions in 5 and extrahepatic lesions in 3 patients overlooked on TrCT; all 8 of these lesions were PET-positive. There was incremental impact on the management of 12.5% (15 of 120) of patients.
  
  
  CONCLUSIONS
  After excluding patients with a normal PET-CT or disseminated disease, there was an incremental diagnostic value of integrated PET-CT imaging in 27% (31 of 120) and incremental impact on management in 12.5% (15 of 120) of patients. CT with contrast did not demonstrate lesions not appreciated by PET-CT.
authors.affiliation: Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232-2675, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Roman
authors.forename: William H
authors.initials: WH
authors.lastname: Martin
authors.forename: Dominique
authors.initials: D
authors.lastname: Delbeke
mesh_terms: D019788:Fluorodeoxyglucose F18; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D009369:Neoplasms / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18