[F-18]MFBG PET/CT outperforming [I-123]MIBG SPECT/CT in the evaluation of neuroblastoma

Purpose Iodine 123 labeled meta-iodobenzylguanidine ([I-123]MIBG) scan with SPECT/CT imaging is one of the most commonly used imaging modalities in the evaluation of neuroblastoma. [F-18]-meta-fluorobenzylguanidine ([F-18]MFBG) is a novel positron emission tomography (PET) tracer which was reported to have a similar biodistribution to [I-123]MIBG. However, the experience of using [(18F)]MFBG PET/CT in the evaluation of patients with neuroblastoma is limited. This preliminary investigation aims to assess the efficacy of [F-18]MFBG PET/CT in the evaluation of neuroblastomas in comparison to [I-123] MIBG scans with SPECT/CT. Materials and methods In this prospective, single-center study, 40 participants (mean age 6.0 +/- 3.7 years) with history of neuroblastoma were enrolled. All children underwent both [I-123]MIBG SPECT/CT and [F-18]MFBG PET/CT studies. The number of lesions and the Curie scores revealed by each imaging method were recorded. Results Six patients had negative findings on both [I-123] MIBG and [F-18]MFBG studies. Four of the 34 patients (11.8%) were negative on [I-123]MIBG but positive on [F-18]MFBG, while 30 patients were positive on both [I-123]MIBG and [F-18] MFBG studies. In these 34 patients, [F-18]MFBG PET/CT identified 784 lesions while [I-123]MIBG SPECT/CT detected 532 lesions ( p < 0.001). The Curie scores obtained from [F-18]MFBG PET/CT (11.32 +/- 8.18, range 1-27) were statistically higher (p < 0.001) than those from [I-123]MIBG SPECT/CT (7.74 +/- 7.52, range 0-26). 30 of 34 patients (88.2%) with active disease on imaging had higher Curie scores based on the [F-18]MFBG study than on the [I-123]MIBG imaging. Conclusion [F-18]MFBG PET/CT shows higher lesion detection rate than [I-123]MIBG SPECT/CT in the evaluation of pediatric patients with neuroblastoma.