PET/CT with 18F-choline: Physiological whole bio-distribution in male and female subjects and diagnostic pitfalls on 1000 prostate cancer patients

Introduction: The C-11/F-18-choline is a PET/CT radiopharmaceutical useful in detecting tumors with high lipogenesis. C-11/F-18-choline uptake can occur in physiological conditions or tumors. The knowledge of its bio-distribution is essential to recognize physiologic variants or diagnostic pitfalls. Moreover, few information are available on the biodistribution of this tracer in female patients. Our aim was to discuss some documented F-18-choline PET/CT pitfalls in prostate cancer patients. Our secondary aim was to describe the F-18-choline bio-distribution in the female body. Methods: We collected diagnostic pitfalls in three PET centers examining 1000 prostate cancer by F-18-choline PET/ CT. All pitfalls were ensured by follow-up, imaging and/or histology. We also performed whole body F-18-choline PET/CT in 5 female patients. Results: 169/1000 (16.9%) patients showed pitfalls not owing to prostate cancer. These findings were due to inflammation, benign tumors while, in 1% of examined patients, a concomitant neoplasm was found. In the female body, the breast showed low physiological uptake. Conclusions: The accurate knowledge of F-18-choline PET/CT bio-distribution and diagnostic pitfalls is essential. Correlative imaging and histological exam are often necessary to depict pitfalls. In women, the uptake in the breast is due to the physiological gradient of F-18-choline uptake in the exocrine glands. Advances in knowledge: Our results confirm the possibility of F-18-choline uptake in several diseases other than prostate cancer. However, our experience was acquired on a large population and shows that a conspicuous amount of F-18-choline diagnostic pitfalls are easily recognizable and attributable to inflammation. A new advance in knowledge is the minimal difference in terms of physiological tracer bio-distribution between male and female patients. (C) 2017 Elsevier Inc. All rights reserved.