Comparison of 18F-fluorodeoxyglucose PET and 68Ga-fibroblast Activation Protein Inhibitor PET in Head and Neck Cancers: A Systematic Review and Meta-analysis.

Objective: This study aimed to compare the diagnostic efficiency of 68Ga-fibroblast activation protein inhibitor (FAPI) positron emission tomography (PET) and 18F-fluorodeoxyglucose (18F-FDG) PET in patients with head and neck cancer (HNC).

Methods: PubMed, Embase, Web of Science, and the Cochrane Library were used to perform a systemic search through June 26, 2024. Methods: Studies comparing the diagnostic value of 68Ga-FAPI PET and 18F-FDG PET in patients with HNC were included. We performed a bivariate meta-analysis of diagnostic data and a meta-analysis of the quantitative parameters. The summary receiver operating characteristic curve was plotted, and publication bias was evaluated via Egger's test.

Results: The meta-analysis included 12 studies on 386 patients with HNC. 68Ga-FAPI PET had superior pooled sensitivity to 18F-FDG PET in detecting primary/recurrent tumors and distant metastases in both lesion-based analysis and patient-based analysis. Although the sensitivity of 18F-FDG PET for detecting lymph node metastases was greater than that of 68Ga-FAPI PET (0.93 [95% CI 0.83-0.97] vs. 0.82 [95% CI 0.63-0.93]), the specificity of 18F-FDG PET was lower than that of 68Ga-FAPI PET (0.36 [95% CI 0.01-0.96] vs. 0.97 [95% CI 0.53-1.00]). In addition, 68Ga-FAPI PET had a higher pooled mean maximum standardized uptake value for distant metastases (3.28 [95% CI 1.90-4.66]) and a higher pooled mean tumor-to-background ratio for primary/recurrent tumors (1.24 [95% CI 0.44-2.04]) than 18F-FDG PET.

Conclusions: Compared to 18F-FDG PET, 68Ga-FAPI PET has superior diagnostic accuracy in HNC lesions. Thus, 68Ga-FAPI PET may be a better tool for staging and restaging than 18F-FDG PET in patients with HNC.