Analysis of the use of [68Ga]Ga-FAPI and [18F]FDG PET/CT for diagnosing and staging non-small cell lung cancer

Abstract Purpose The current research was developed for comparing the relative diagnostic utility of [68Ga]Ga-FAPI PET/CT and [18F]FDG PET/CT when evaluating initial tumors and metastases in non-small cell lung cancer (NSCLC) patients. Methods A prospective analysis of 28 individuals with histopathologically confirmed NSCLC that underwent [68Ga]Ga-FAPI and [18F]FDG PET/CT imaging was conducted. The relative performance of these different imaging modalities was compared based upon visual assessment, rates of cancer detection, and metabolic parameters (target-to-background ratio [TBR], maximum standard uptake value [SUVmax]) for both primary tumors and metastases. Results In total, this study enrolled 28 cases (13 male, 15 female; median age: 60.5 years, range: 34–78 years. [68Ga]Ga-FAPI PET/CT imaging was found to more effectively discern both metastases and primary tumors as compared to [18F]FDG PET/CT imaging, detecting more primary tumors (28 vs. 27), as well as metastases present within the lymph nodes (53 vs. 49), pleura (8 vs. 7), liver (4 vs. 1), and bone (41 vs. 35). In contrast, [68Ga]Ga-FAPI PET/CT was not capable of detecting as many adrenal metastases as was [18F]FDG PET/CT imaging (0 vs. 2). The SUVmax and TBR values for [68Ga]Ga-FAPI were substantially superior to those for [18F]FDG in lymph node, pleural, and bone metastases. While the SUVmax for these two imaging approaches was comparable for hepatic metastases, [68Ga]Ga-FAPI exhibited a significantly higher TBR in relation to that of [18F]FDG. [68Ga]Ga-FAPI additionally exhibited greater accuracy than that achieved for [18F]FDG PET/CT when used to conduct NSCLC patient N-staging (80% [8/10] vs. 50% [5/10]) and M-staging (92.9% [26/28] vs. 89.3% [25/28]). Conclusions These data highlight the value of [68Ga]Ga-FAPI PET/CT imaging as an approach of diagnosing and staging NSCLC, improving the diagnosis of most metastases and facilitating the superior staging of NSCLC patients relative to that achieved by [18F]FDG PET/CT.