Objectives: The study is to evaluate biodistribution, dosimetry, safety, and clinical usefulness of F-AlF-NOTA-octreotide (F-OC) PET/CT in combination with F-FDG PET/CT for detection of neuroendocrine neoplasms (NENs).
Methods: The biodistribution, dosimetry, and safety of F-OC were evaluated in 3 healthy volunteers. Twenty-two NEN patients underwent PET/CT at 60 minutes after intravenous injection of 3.7 to 4.44 MBq (0.1-0.12 mCi) per kilogram of body weight of F-OC. This was followed by F-FDG PET/CT within a 2-week period.
Results: F-OC was well tolerated by all healthy volunteers and NEN patients. The calculated effective dose of F-OC was 0.023 ± 0.002 mSv/MBq. In NEN patients, we observed prominent F-OC tumor uptake and high tumor-to-background ratios. Tumor uptake of F-OC was greater than that of F-FDG, and this was particularly evident in G2 NENs (median SUVmax, 45.6 vs 4.3; P < 0.015). Tumor uptake of F-OC or F-FDG was significantly correlated with tumor differentiation (P < 0.05). Dual tracer PET/CT detected more lesions and also yielded information on the biological status of tumors.
Conclusions: The tracer F-OC exhibited favorable safety and dosimetry profiles. F-OC provided superior imaging of well-differentiated NENs and significantly higher tumor-to-background ratio compared with F-FDG. Combining F-FDG with F-OC PET/CT has the potential to improve NEN staging and management of patient treatment.