[18F]FDG PET/CT is Superior to [68Ga]Ga-FAPI PET/CT for Lesion Detection in Extranodal NK/T-cell Lymphoma, Nasal Type

Background: This study aimed to assess the feasibility of [ 68 Ga]Ga-FAPI PET/CT for detecting lesions in extranodal NK/T-cell lymphoma, nasal type (ENKTL-NT), and to compare its diagnostic performance with [ 18 F]FDG PET/CT in clinical practice. Patients and Methods: Between December 2022 and December 2023, 19 patients with pathologically confirmed ENKTL-NT at West China Hospital underwent baseline [ 68 Ga]Ga-FAPI and [ 18 F]FDG PET/CT. Lesions were documented by each modality, and detection rates compared at both patient and lesion levels. Results: Among the 19 patients, a total of 117 lesions were identified (66 nodal and 51 extranodal). At the patient level, the detection rate was 94.7% (18/19) for [ 68 Ga]Ga-FAPI versus 100% (19/19) for [ 18 F]FDG. At the lesion level, rates were 54.7% (64/117) versus 99.1% (116/117), respectively. Conclusions: [ 68 Ga]Ga-FAPI PET/CT is less effective than [ 18 F]FDG PET/CT in detecting ENKTL-NT lesions.