Uptake Patterns of Peripheral Ganglia on 18F-MFBG PET/CT in Neuroblastoma Patients.

PURPOSE: 18F-MFBG is a novel PET radiotracer increasingly utilized for neuroblastoma evaluation. Notably, it exhibits uptake in certain normal anatomical structures and some benign conditions in patients. This study aims to characterize the 18F-MFBG uptake patterns in the ganglia of neuroblastoma patients, and explore the imaging features that differentiate between ganglia and metastatic lymph nodes. METHODS: A retrospective analysis was performed using imaging and clinical data from pediatric patients diagnosed with neuroblastoma who underwent 18F-MFBG PET/CT at the Beijing Friendship Hospital, Capital Medical University between September 2025 and June 2026. Imaging was used to evaluate the uptake in peripheral ganglia, normal organs, primary tumors, and metastatic lymph nodes. RESULTS: 18F-MFBG uptake was observed in at least one peripheral ganglia in 173( 48.32%) patients. Grossly visible 18F-MFBG uptake was observed in the cervical ganglia (117, 32.68%), stellate ganglia (126, 35.20%), celiac ganglia (35, 9.78%), and sacral ganglia (18, 5.03%), respectively. No significant statistical difference in 18F-MFBG uptake between the left and right sides for all ganglia except the celiac ganglia (P = 0.003). Uptake in ganglia was associated with male sex, older age, and higher uptake in the thyroid gland, aorta, pancreas, and kidney. Longitudinal imaging confirmed that ganglia uptake remained highly stable. The SUVmax in the stellate ganglia was lower than metastatic cervical lymph nodes. The cutoff value of 2.88 can effectively distinguish metastatic cervical lymph nodes from the stellate ganglia, which generated sensitivity and specificity of 0.97 and 0.76, combined with an AUC of 0.89. Using a cutoff value of 2.81, metastatic celiac lymph nodes were reliably distinguished from the celiac ganglia, providing a sensitivity of 0.86 and a specificity of 0.78, and an AUC of 0.82. CONCLUSION: Uptake in ganglia on 18F-MFBG PET/CT is a common, mild, and chronologically stable phenomenon in pediatric neuroblastoma, exhibiting a descending prevalence from the stellate ganglia to the cervical, celiac, and sacral ganglia. And the uptake is typically stable and mild. Integrating cross-sectional CT morphological features with PET quantitative metrics allows for the reliable differentiation of normal sympathetic ganglia from regional metastatic celiac lymph nodes.