Diagnostic value of 18F-FDG PET/CT in paediatric neuroblastoma: comparison with 131I-MIBG scintigraphy.

Purpose: The aim of the study was to evaluate the diagnostic value of fluorine-18 fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in paediatric patients with neuroblastoma (NB) and compare the results with iodine-131 metaiodobenzylguanidine (131I-MIBG) scintigraphy.

Methods: Data on 40 paediatric patients (age, 5.5 ± 5.6 years; male, 32; female, eight) with histopathologically proven NB who underwent 18F-FDG PET/CT (staging, 21 patients; restaging/response monitoring, 19 patients) were retrospectively evaluated. I-MIBG scintigraphy data were available for 28/40 patients (median interval, 15 days; staging, 20 patients; restaging/response monitoring, eight patients). 131I-MIBG scintigraphy and 18F-FDG PET/CT images were evaluated by two nuclear medicine physicians in consensus and in separate sessions. Histopathology (n = 50 lesions) and/or clinical/imaging follow-up (n = 90 lesions) data were taken as the reference standard.

Results: Patient-wise sensitivity, specificity, positive-predictive value, negative-predictive value and accuracy of 18F-FDG PET/CT were 100, 50, 91.89, 100 and 92.50%, respectively. A total of 140 lesions (primary, 37; lymph node, 31; bone, 50; bone marrow, 15; and others, seven) were detected on PET/CT. In 28 patients undergoing both imaging studies, the sensitivity, specificity, positive-predictive value, negative-predictive value and accuracy of 18F-FDG PET/CT were 100, 60, 92, 100 and 92.80%, respectively, and those of 131I-MIBG were 95.65, 60, 91.67, 75 and 89.20%, respectively. In these 28 patients, PET/CT detected 107 lesions (primary, 25; lymph node, 22; bone/bone marrow, 56; and others, four) and 131I-MIBG scintigraphy detected 74 lesions (primary, 24; lymph node, five; and bone/bone marrow, 45). On a patient-based comparison there was no significant difference between 18F-FDG PET/CT and 131I-MIBG (P = 1.000), but 18F-FDG PET/CT was superior to 131I-MIBG on a lesion-based comparison (P < 0.0001). Although no difference was noted for primary lesions (P = 1.000), PET/CT was superior to 131I-MIBG scintigraphy for the detection of lymph nodal (P = 0.001) and bone/bone marrow lesions (P = 0.007).

Conclusion: 18F-FDG PET/CT shows high accuracy in paediatric patients with NB and demonstrates more lesions as compared with 131I-MIBG scintigraphy.