The added value of [ 68 Ga]Ga-DOTA-FAPI-04 PET/CT in pancreatic cancer: a comparison to [ 18 F]F-FDG

Objectives We aimed to compare the diagnostic and prognostic performance of [ 68 Ga]Ga-DOTA-FAPI-04 and [ 18 F]FDG PET/CT in pancreatic cancer. Methods This single-center retrospective study enrolled 51 patients who underwent [ 68 Ga]Ga-DOTA-FAPI-04 and [ 18 F]FDG PET/CT. The final diagnosis on PET/CT images was verified by histopathology or 1-year follow-up. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [ 18 F]FDG and [ 68 Ga]Ga-DOTA-FAPI-04 PET/CT were calculated to compare the diagnostic efficacy. Progression-free survival (PFS) was the endpoint for the survival analysis. Twenty-six patients were eligible for the Kaplan–Meier survival analysis using a log-rank test. And multivariate analysis including age, sex, stage, CA199 level, and SUV max of [ 18 F]FDG and [ 68 Ga]Ga-DOTA-FAPI-04 was also performed. Two-tailed p < 0.05 was considered statistically significant. Results [ 68 Ga]Ga-DOTA-FAPI-04 showed a higher sensitivity than [ 18 F]FDG for detecting primary tumor (100% vs. 95.0%), metastatic lymph nodes (96.2% vs. 61.5%), and distant metastases (100% vs. 84.0%) ( p < 0.0001, respectively). For [ 68 Ga]Ga-DOTA-FAPI-04, the tumor-to-liver background ratio (TLBR) of liver metastases was higher (5.7 ± 3.2 vs. 3.2 ± 1.3, p < 0.0001). Furthermore, SUV max > 14.9 on [ 68 Ga]Ga-DOTA-FAPI-04 was significantly associated with PFS rates (chi-square = 12.05, p = 0.001). The Cox regression analysis showed that SUV max of [ 68 Ga]Ga-DOTA-FAPI-04 was an independent prognostic factor for PFS ( p = 0.001; hazard ratio, 8.877). Conclusions [ 68 Ga]Ga-DOTA-FAPI-04 PET/CT showed a higher sensitivity and accuracy than [ 18 F]FDG PET/CT in diagnosing pancreatic cancer and might have an independent prognostic value for pancreatic cancer patients. Key Points • [ 68 Ga]Ga-DOTA-FAPI-04 PET/CT had a higher sensitivity and accuracy in detecting primary tumors, metastatic lymph nodes, and distant metastases than [ 18 F]FDG PET/CT. • SUV max > 14.9 on [ 68 Ga]Ga-DOTA-FAPI-04 PET/CT before chemotherapy was significantly associated with progress-free status rates (chi-square = 12.05, p = 0.001) in pancreatic cancer patients.