[68Ga]Ga-Fapi-2286 Pet Imaging in Pediatric Midline Gliomas: Preliminary Findings and Clinical Implications Publisher



S Farzanehfar SAEED ; S Mirabedian SOHEILA ; A Kiumarsi AZADE ; M Abbasi MEHRSHAD ; N Pak NEDA ; M Nazari MOSTAFA ; M Ebrahimi MARZIEH ; M Farzin MOSTAFA ; Z Paymani ZEINAB
Source: Clinical and Translational Imaging Published:2025

Abstract

Background: Regarding the poor prognosis, limited efficacy of standard therapies, and scarce data on FAPI imaging in pediatric midline gliomas, we conducted this pilot study to investigate the potential role of [68Ga]Ga-FAPI-2286 PET/CT for improved diagnosis and possible theranostic applications in these high-risk tumors. Objective: The study aims to evaluate the diagnostic efficacy and potential theranostic implications of [68Ga]Ga-FAPI-2286 PET/CT imaging in pediatric patients with midline gliomas. Methods: This prospective small cohort study involved six pediatric patients aged 5–13 years diagnosed with midline gliomas (four diffuse intrinsic pontine gliomas [DIPGs], one midbrain, and one thalamic). Intravenous administration of [68Ga]Ga-FAPI-2286 (1.8–2.2 MBq/kg) was followed by PET/CT scan 45 min later. Lesion uptake (SUVmax) and tumor-to-background ratios (TBR) were measured. Comparison analyses were done between DIPG vs. non-DIPG and high-grade vs. low-grade tumors. Results: SUVmax varied widely (0.06–2.24), as did TBR (6–224). Non-DIPG tumors demonstrated higher uptake (mean SUVmax: 1.84, TBR: 184) compared to DIPG tumors (mean SUVmax: 0.34, TBR: 9), though differences were not statistically significant (SUVmax, p = 0.057; TBR, p = 0.091). Similarly, no significant differences were observed between high-grade and low-grade tumors. Tumors in the thalamus and midbrain showed generally higher uptake compared to pontine locations. Conclusion: [68Ga]Ga-FAPI-2286 PET imaging showed limited utility in pediatric midline gliomas, particularly DIPGs, due to inherently low fibroblast activation protein (FAP) expression and possibly intact blood-brain barriers. Larger, more controlled studies are necessary to clarify the theranostic potential of FAPI PET in pediatric neuro-oncology. © 2025 Elsevier B.V., All rights reserved.