68Ga-FAPI-46 PET/CT in the evaluation of gliomas: comparison with 18F-FDG PET/CT and contrast-enhanced MRI

Dan Ruan; Jianping Sun; Chengkun Han; Jiayu Cai; Lingyu Yu; Liang Zhao; Yizhen Pang; Changjing Zuo; Long Sun; Zhanxiang Wang; Guowei Tan; Xiaobo Qu; Haojun Chen

doi:10.7150/thno.103399

⁶⁸Ga-FAPI-46 PET/CT in the evaluation of gliomas: comparison with ¹⁸F-FDG PET/CT and contrast-enhanced MRI

Theranostics. 2024 Oct 21;14(18):6935-6946. doi: 10.7150/thno.103399. eCollection 2024.

Authors

Dan Ruan^{1

2}, Jianping Sun¹, Chengkun Han³, Jiayu Cai¹, Lingyu Yu¹, Liang Zhao¹, Yizhen Pang¹, Changjing Zuo⁴, Long Sun¹, Zhanxiang Wang^{5

6}, Guowei Tan⁵, Xiaobo Qu^{2

3}, Haojun Chen^{1

6}

Affiliations

¹ Department of Nuclear Medicine and Minnan PET Center, Xiamen Key Laboratory of Radiopharmaceuticals, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
² National Institute for Data Science in Health and Medicine, Department of Electronic Science, Intelligent Medical Imaging R&D Center, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, China.
³ Department of Radiology, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
⁴ Department of Nuclear Medicine, Changhai Hospital, Naval Medical University, Shanghai, China.
⁵ Department of Neurosurgery, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
⁶ Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, China.

Abstract

Rationale: This study compared ⁶⁸Ga-FAPI-46 PET/CT, ¹⁸F-fluorodeoxyglucose (FDG) PET/CT, and contrast-enhanced MRI (CE-MRI) for glioma imaging, classification, and recurrence detection and explored PET parameters and molecular pathological profiles. Methods: Between June 2020 and June 2024, we prospectively enrolled patients with space-occupying lesions in the brain or previously treated gliomas. All patients underwent sequential CE-MRI, ⁶⁸Ga-FAPI-46, and ¹⁸F-FDG PET/CT. Diagnostic accuracy was assessed based on a reference standard, and PET parameters were analysed for correlations with WHO grading and molecular characteristics. Results: Forty-eight patients (median age, 51 years; 32 men) with 40 confirmed gliomas were enrolled. For primary tumour diagnosis, the sensitivity of ⁶⁸Ga-FAPI-46 PET/CT was equivalent to CE-MRI (95% vs. 100%, P = 0.99) and ¹⁸F-FDG PET/CT (95% vs. 77%, P = 0.13). ⁶⁸Ga-FAPI-46 uptake was higher in grade IV than in grade I-II gliomas (5.03 vs. 1.14, P = 0.02). ⁶⁸Ga-FAPI-46 PET/CT showed significantly higher maximum standardized uptake value and tumour-to-background ratio (TBR) in recurrent tumours than in treatment-related changes and demonstrated favourable sensitivity and specificity for detecting recurrent gliomas, though not significantly superior to ¹⁸F-FDG PET/CT (sensitivity: 100% vs. 85%, P = 0.48; specificity: 100% vs. 80%, P = 0.99) and CE-MRI (sensitivity: 100% vs. 100%, P = NA; specificity: 100% vs. 40%, P = 0.25). Glial fibrillary acidic protein-mutant gliomas exhibited higher ⁶⁸Ga-FAPI-46 uptake than wild-type gliomas. Conclusion: ⁶⁸Ga-FAPI-46 PET/CT outperformed ¹⁸F-FDG and CE-MRI in diagnosing glioma recurrence, although the results were not statistically significant. For primary glioma diagnosis, ⁶⁸Ga-FAPI-46 PET/CT, despite having a better TBR, did not surpass ¹⁸F-FDG PET/CT and CE-MRI in terms of sensitivity and specificity. However, ⁶⁸Ga-FAPI-46 PET/CT is superior to ¹⁸F-FDG for visualizing and classifying gliomas.

Keywords: 18F-FDG; 68Ga-FAPI-46 PET/CT; CE-MRI; recurrent detection.

Publication types

Comparative Study

MeSH terms

Adult
Aged
Brain Neoplasms* / diagnostic imaging
Brain Neoplasms* / pathology
Contrast Media
Coordination Complexes
Female
Fluorodeoxyglucose F18*
Glioma* / diagnostic imaging
Glioma* / pathology
Humans
Magnetic Resonance Imaging* / methods
Male
Middle Aged
Neoplasm Recurrence, Local / diagnostic imaging
Positron Emission Tomography Computed Tomography* / methods
Prospective Studies
Quinolines
Radiopharmaceuticals*
Sensitivity and Specificity

Substances

Fluorodeoxyglucose F18
Radiopharmaceuticals
68Ga-FAPI
Contrast Media
Coordination Complexes
Quinolines