Comparison of 18F-FDG and 68Ga-FAPI-04 Uptake in Postoperative Re-evaluation of Gastric, Duodenal, and Colorectal Cancers

Abstract

Purpose To compare the potential efficacy of 68Ga-FAPI-04 PET/CT with that of 18F-FDG PET/CT for detecting tumor recurrence and nodal and distant metastases in gastric, duodenal, and colorectal cancers. Methods This single-center retrospective clinical study was performed at the Affiliated Hospital of Southwest Medical University between January 2020 and June 2022. Participants with gastric, duodenal, and colorectal cancers after curative resection underwent both 68Ga-FAPI-04 and 18F-FDG PET/CT. Histopathologic examination, morphologic imaging, and/or follow-up imaging served as the reference standards. The SUVmax of the tumor recurrence and nodal and distant metastases between 18F-FDG and 68Ga-FAPI-04 PET/CT were compared using the paired-sample t test. Results Forty-one participants with gastric, duodenal, and colorectal cancers were enrolled in the study (median age, 51 years; range, 19–75 years). The sensitivity of 68Ga-FAPI-04 PET/CT was higher than that of 18F-FDG PET/CT for detecting tumor recurrence (6 of 6 [100%] vs 4 of 6 [67%]), nodal metastases (92 of 92 [100%] vs 31 of 92 [34%]), and distant metastases (28 of 30 [93%] vs 20 of 30 [67%]). Conclusion 68Ga-FAPI-04 PET/CT for tumor re-evaluation showed potential for more accurate performance of gastric, duodenal, and colorectal cancers, thereby improving treatment decision-making.