Clinical application of Al 18 F-NOTA-FAPI PET/CT in diagnosis and TNM staging of pancreatic adenocarcinoma, compared to 18 F-FDG.

PURPOSE: This study aimed to investigate the ability of Al18 F-NOTA-FAPI PET/CT to diagnose pancreatic carcinoma and tumor-associated inflammation with the comparison of 18 F-FDG PET/CT.

METHODS: Prospective analysis of Al18 F-NOTA-FAPI PET/CT and 18 F-FDG PET/CT scans of 31 patients from 05/2021 to 05/2022 were analyzed. Al18 F-NOTA-FAPI imaging was performed in patients who had Ce-CT and FDG PET/CT and the diagnosis was still unclear. Follow-up histopathology or radiographic examination confirmed the findings. Radiotracer uptake, diagnostic performance, and TNM (tumor-node-metastasis) classifications were compared.

RESULTS: A total of 31 patients with pancreatic carcinoma (all were adenocarcinoma) underwent Al18 F-NOTA-FAPI-04 PET/CT, including 20 male and 11 female patients, with a mean age of 58.2 ± 8.5 years. FAPI-04 PET/CT imaging showed a higher value of SUVmax-15min/30min/60min , SUVmean-15min/30min/60min , TBR1 , and TBR2 in pancreatic carcinoma than FDG (all P < 0.01). The mean level of Al18 F-NOTA FAPI-04 uptake values of the pancreatic ductal adenocarcinoma was higher than that of pancreatitis in both SUVmax-30min (P < 0.01), SUVmean-30min (P < 0.05), SUVmax-60min (P < 0.01), and SUVmean-60min (P < 0.01). The FAPI △SUVmax-1 , △SUVmax-2 , and △SUVmean-2 uptake values of pancreatic carcinoma were higher than tumor-associated inflammation (all P < 0.01). TNM staging of 16/31 patients changed after Al18 F-NOTA FAPI-04 PET/CT examination with all upstaging changes.

CONCLUSION: Al18 F-NOTA-FAPI-04 PET/CT at 15 and 30 min also demonstrated an equivalent detection ability of pancreatic lesion to 18 F-FDG PET/CT. Delayed-phase Al18 F-NOTA-FAPI-04 PET/CT can help differentiate pancreatic carcinoma and tumor-associated inflammation. Al18 F-NOTA FAPI-04 PET/CT also performed better than FDG PET/CT in TNM staging.

TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100051406. Registered 23 September 2021, https://www.chictr.org.cn/showproj.html?proj=133033.