Diagnostic Performances of Radiolabeled FAPI PET/CT for Lymph Node Staging in Head and Neck Cancer Patients: Comparison With 18F-FDG PET/CT

Objective: The purpose of the current study was to compare the diagnostic performances of radiolabeled FAPI and 18 F-FDG PET/CT for the detection of lymph node (LN) metastasis in head and neck cancer (HNC) patients. Methods: The PubMed, Cochrane database, and EMBASE database, from the earliest available date of indexing through December 31, 2024, were searched for studies comparing diagnostic performances of radiolabeled FAPI and 18 F-FDG PET/CT for the detection of metastatic LN in HNC patients. We estimated pooled sensitivities and specificities across studies. Results: Across 8 studies (14 results), the pooled sensitivity of FAPI PET/CT was 0.89 and the pooled specificity was 0.93. The pooled sensitivity of 18 F-FDG PET/CT was 0.91 and the pooled specificity was 0.50. On patient-based analysis, the estimated sensitivity and specificity of FAPI were 0.96 and 0.96, and those of 18 F-FDG were 0.95 and 0.34, respectively. On lesion-based analysis, the estimated sensitivity and specificity of FAPI were 0.84 and 0.94, and those of 18 F-FDG were 0.86 and 0.78, respectively. On neck side–based analysis, the estimated sensitivity and specificity of FAPI were 0.88 and 0.79, and those of 18 F-FDG were 0.91 and 0.29, respectively. Conclusions: Radiolabeled FAPI showed a good diagnostic performance for the detection of metastatic LN in HNC patients. Also, 18 F-FDG PET/CT revealed low specificity for LN staging in HNC patients. Future large multicenter research with more patients would be necessary to provide a more comprehensive overview of the usefulness of radiolabeled FAPI for LN staging in HNC patients.