Diagnostic performance of FAPI PET/CT for the detection of lymph node metastases in lung cancer patients: a meta-analysis.

Objective: To evaluate the diagnostic performance of fibroblast activation protein inhibitors (FAPI) PET/CT for the detection of lymph node (LN) metastases in lung cancer patients.

Methods: The PubMed and Embase databases were searched to identify relevant articles published through July 2024. We included studies reporting the diagnostic accuracy of FAPI PET/CT in detecting LN metastases in lung cancer patients. A head-to-head comparison of FAPI PET/CT and fluorodeoxyglucose (FDG) PET/CT was made among available studies. The pooled sensitivity, specificity, and area under the summary receiver-operating characteristics curve (AUC) were determined by using bivariate random-effects model.

Results: Seven studies with 409 patients were eligible. The pooled sensitivity, specificity, and AUC value for FAPI PET/CT in detecting LN metastases in lung cancer patients were 88% (95% CI, 78-93%), 94% (95% CI, 89-96%), and 0.97 (95% CI, 0.95-0.98), respectively. Six studies provided head-to-head comparison data, and the pooled sensitivity, specificity, and AUC value were 89% (95% CI 80-95%), 94% (95% CI 89-97%), and 0.97 (95% CI 0.95-0.98) for FAPI PET/CT versus 78% (95% CI 64-87%), 66% (95% CI 33-88%), and 0.80 (95% CI 0.76-0.83) for FDG PET/CT. Fagan nomogram indicated that when the pre-test probability was set at 26%, the negative post-test probability for a FAPI PET/CT scan could decrease to 4%.

Conclusions: FAPI PET/CT shows excellent diagnostic accuracy for the detection of LN metastases in lung cancer patients, and is superior to standard-of-care FDG PET/CT. The outstanding ruling-out performance of FAPI PET/CT for LN metastases indicates that it holds the potential to reduce invasive diagnostic procedures.