title: 18F-FDG PET/CT and 123I-metaiodobenzylguanidine imaging in high-risk neuroblastoma: diagnostic comparison and survival analysis.
abstract: The aim of our study was to evaluate prospectively the diagnostic performance and prognostic significance of (18)F-FDG PET/CT in comparison with (123)I-metaiodobenzylguanidine ((123)I-MIBG) imaging in patients with high-risk neuroblastoma.
  
  
  METHODS
  Twenty-eight patients with refractory or relapsed high-risk neuroblastoma (16 male and 12 female patients; age range, 2-45 y; median age, 7.5 y) were simultaneously evaluated with (18)F-FDG PET/CT and (123)I-MIBG imaging before treatment with high-dose (131)I-MIBG. We compared the 2 methods in mapping tumor load, according to the extent of disease and intensity of positive lesions identified in each patient. Separate comparisons were performed for the soft-tissue and bone-bone marrow components of tumor burden. Survival analysis was performed to assess the prognostic significance of (18)F-FDG and (123)I-MIBG imaging parameters.
  
  
  RESULTS
  (18)F-FDG PET/CT results were positive in 24 of 28 (86%) patients, whereas (123)I-MIBG imaging results were positive in all patients. (18)F-FDG was superior in mapping tumor load in 4 of 28 (14%) patients, whereas (123)I-MIBG was better in 12 of 28 (43%) patients. In the remaining 12 (43%) patients, no major differences were noted between the 2 modalities. (18)F-FDG PET/CT missed 5 cases of bone-bone marrow disease, 4 cases of soft-tissue disease, and 6 cases of skull involvement that were positive on (123)I-MIBG scans. Cox regression and Kaplan-Meier survival curves showed that the group of patients (4/28) in whom (18)F-FDG was superior to (123)I-MIBG had a significantly lower survival rate than the others. Tumoral avidity for (18)F-FDG (maximum standardized uptake value) and extent of (18)F-FDG-avid bone-bone marrow disease were identified as adverse prognostic factors.
  
  
  CONCLUSIONS
  (123)I-MIBG imaging is superior to (18)F-FDG PET/CT in the assessment of disease extent in high-risk neuroblastoma. However, (18)F-FDG PET/CT has significant prognostic implications in these patients.
authors.affiliation: Institute of Nuclear Medicine, University College London Hospital, London, United Kingdom.
authors.forename: Nikolaos D
authors.initials: ND
authors.lastname: Papathanasiou
authors.forename: Mark N
authors.initials: MN
authors.lastname: Gaze
authors.forename: Kevin
authors.initials: K
authors.lastname: Sullivan
authors.forename: Matthew
authors.initials: M
authors.lastname: Aldridge
authors.forename: Wendy
authors.initials: W
authors.lastname: Waddington
authors.forename: Ahmad
authors.initials: A
authors.lastname: Almuhaideb
authors.forename: Jamshed B
authors.initials: JB
authors.lastname: Bomanji
mesh_terms: D019797:3-Iodobenzylguanidine; D000293:Adolescent; D000328:Adult; D019046:Bone Marrow Neoplasms / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D053208:Kaplan-Meier Estimate; D008113:Liver Neoplasms / Q000000981:diagnostic imaging; D008297:Male; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging; D009364:Neoplasm Recurrence, Local; D009447:Neuroblastoma / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D013534:Survival; D016019:Survival Analysis; D014055:Tomography, Emission-Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D019797:3-Iodobenzylguanidine