[18F]mFBG PET/CT surpasses [18F]FDG PET/CT for evaluation of pediatric neuroblastoma

Purpose [ 18 F]FDG PET/CT serves as an alternative imaging modality for neuroblastoma in cases where [ 123 I]MIBG yields negative results or is unavailable. [ 18 F]mFBG, a novel PET tracer for neuroblastoma imaging, requires further clinical validation. This preliminary study aims to evaluate the efficacy of [ 18 F]mFBG PET/CT compared to [ 18 F]FDG PET/CT in detecting neuroblastoma. Methods In this retrospective investigation, 56 pediatric patients were enrolled. Each patient underwent both [ 18 F]mFBG PET/CT and [ 18 F]FDG PET/CT within one week. Two children underwent a second paired [ 18 F]FDG-[ 18 F]mFBG PET/CT scan. In total, 58 paired scans (mean age 47.6 ± 38.0 months, range 6–108 months) were performed. Two experienced readers measured normal organ uptake (SUV mean ), lesion uptake (SUV max ), and tumor-to-background ratio (TBR). A lesion-by-lesion analysis was conducted to compare detection rates between [ 18 F]mFBG and [ 18 F]FDG. Results Twenty paired scans exhibited negative findings on both [ 18 F]mFBG and [ 18 F]FDG studies. Among the remaining 38 scans, 8 (21.05%) were [ 18 F]mFBG-positive/[ 18 F]FDG-negative, 1 (2.63%) was [ 18 F]FDG-positive/[ 18 F]mFBG-negative, and 29 (76.32%) were positive on both tracers. In these 38 scans, [ 18 F]mFBG PET/CT identified 431 lesions, whereas [ 18 F]FDG PET/CT detected only 162 lesions (p<0.001). Six of eight [ 18 F]mFBG-positive/[ 18 F]FDG-negative cases were histopathologically confirmed as neuroblastoma. The mean TBR of [ 18 F]mFBG PET/CT(6.68 ± 5.76) was significantly higher (p<0.001) than that of [ 18 F]FDG PET/CT (4.49 ± 2.88). Conclusion [ 18 F]mFBG PET/CT detected more neuroblastoma lesions than [ 18 F]FDG PET/CT, suggesting it may be a more viable alternative when standard [ 123 I]MIBG scanning is not feasible.