Comparison of [(68)Ga]Ga-DOTA-FAPI-04 and [(18)F]FDG Uptake in Esophageal Cancer

PURPOSE: Accurate clinical staging is crucial to managing esophageal cancer. [(68)Ga]Ga-DOTA-FAPI-04 exhibits good diagnostic performance in various tumors, showing a promising alternative to [(18)F]FDG. Here, we investigated the diagnostic performance of [(68)Ga]Ga-DOTA-FAPI-04 PET/CT and [(18)F]FDG PET/CT in the diagnosis of primary and metastatic lesions of esophageal cancer. METHODS: Patients with esophageal cancer who underwent concurrent [(68)Ga]Ga-DOTA-FAPI-04 and [(18)F]FDG PET/CT between January 2020 and June 2021 were retrospectively analyzed. [(68)Ga]Ga-DOTA-FAPI-04 and [(18)F]FDG PET/CT uptakes were compared by using the paired samples t test. The McNemar test was used to compare the diagnostic performance between the two techniques. RESULTS: Thirty-five patients (ranging from 44-83 years old with a median age of 63.5 years) were evaluated in our study. In treatment-naive patients (n=25), [(68)Ga]Ga-DOTA-FAPI-04 PET could detect all esophageal cancers, whereas 1 patient with superficial esophageal cancer was negative in FDG but positive in [(68)Ga]Ga-DOTA-FAPI-04 (T1). [(68)Ga]Ga-DOTA-FAPI-04 uptake was higher than [(18)F]FDG in primary lesions (13.8 ± 6.9 vs 10.9 ± 6.8, respectively, P=0.004), involved lymph nodes (9.3 ± 5.2 vs 6.4 ± 5.9, respectively, P=0.002), and bone and visceral metastases (10.4 ± 6.0 vs 6.1 ± 7.5, respectively, P=0.001). In addition, [(68)Ga]Ga-DOTA-FAPI-04 PET/CT has a higher detection sensitivity than [(18)F]FDG PET/CT for primary tumors [100% (25/25) vs. 96.0% (24/25), respectively], lymph nodes [95.0% (57/60) vs 75.0% (45/60), P<0.001], and bone and visceral metastases [100% (25/25) vs 72% (18/25), respectively; P= 0.008]. CONCLUSION: [(68)Ga]Ga-DOTA-FAPI-04 PET/CT has higher tracer uptake value and is superior to [(18)F]FDG PET/CT in detecting primary and metastatic lesions in patients with esophageal cancer.