[18F] AlF‑NOTA‑FAPI‑04 PET/CT as a promising tool for imaging fibroblast activation protein in gastrointestinal system cancers: a prospective investigation of comparative analysis with 18F-FDG

• Published in: European journal of nuclear medicine and molecular imaging 2023-11, Vol.50 (13), p.4051-4063
• Main Authors: Yang, Liping, Xu, Shichuan, Cheng, Liang, Gao, Chao, Cao, Shaodong, Chang, Zhengsong, Wang, Kezheng
• Format: Article
• Language: English
• Subjects: Cancer; Cardiology; Comparative analysis; Computed tomography; Diagnosis; Fibroblast activation protein; Fluorine isotopes; Gastrointestinal system; Imaging; Lesions; Lymph nodes; Lymphatic system; Malignancy; Medicine; Medicine & Public Health; Metastases; Metastasis; Neuroimaging; Nuclear Medicine; Oncology; Original; Original Article; Orthopedics; Patients; Pharmaceuticals; Positron emission; Positron emission tomography; Radiochemical analysis; Radioisotopes; Radiology; Sensitivity analysis; Tumors
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-023-06351-9

Purpose The radiopharmaceutical [ 18 F]AlF-NOTA-FAPI-04 presents a promising alternative to 68  Ga-FAPI owing to its relatively longer half-life. This study aimed to evaluate the clinical usefulness of [ 18 F]AlF-NOTA-FAPI-04 PET/CT for the diagnosis of primary and metastatic lesions in various types of gastrointestinal system cancers, compared with 18 F-FDG PET/CT. Methods Patients diagnosed with gastrointestinal system malignancies were prospectively enrolled. All patients underwent both 18 F-FDG and 18 F-FAPI-04 PET/CT scans within one week, with 44 (73.3%) for cancer staging and 16 (26.7%) for tumor restaging. Diagnostic efficacy of the primary tumor, as well as the presence and number of lymph nodes and distant metastases, were assessed. Tumor uptake was quantified by the maximum standard uptake value (SUVmax). Results For detection of primary tumor, the diagnostic sensitivity of 18 F-FDG PET/CT was 72.7%, while it was 97.7% for 18 F-FAPI-04 PET/CT. Based on per-lymph node analysis, the sensitivity, specificity, and accuracy of 18 F-FAPI-04 PET/CT in diagnosing metastatic lymph nodes were 91.89%, 92.00%, and 91.96%, respectively. These values were notably higher than those 18 F-FDG PET/CT (79.72%, 81.33% and 80.80%, respectively). The 18 F-FAPI-04 PET/CT surpassed 18 F-FDG PET/CT in detecting suspected metastases in the brain (7 vs. 3), liver (39 vs. 20), bone (79 vs. 51), lung (11 vs. 4), and peritoneal carcinoma (48 vs. 22). Based on per-patient analysis, differential diagnostic accuracies ( 18 F-FAPI-04 vs. 18 F-FDG PET/CT) were observed in all patients (91.7% vs. 76.7%), the initial staging group (90.9% vs. 79.5%), and the re-staging group (93.8% vs. 68.7%). Additionally, 18 F-FAPI-04 PET/CT revised final diagnosis in 31.7% of patients, contrasting with 18 F-FDG PET/CT, and prompted changes in clinical management for 21.7% of the patients. Conclusion 18 F-FAPI-04 PET/CT outperforms 18 F-FDG PET/CT in delineating the primary gastrointestinal tumors and detecting suspected metastatic lesions due to a higher target-to-background ratio (TBR). Moreover, 18 F-FAPI-04 PET/CT could provide valuable guidance for tumor staging, thereby having a potential impact on patient management.