Fluorine-18-Labeled Fluciclovine PET/CT in Clinical Practice: Factors Affecting the Rate of Detection of Recurrent Prostate Cancer.

OBJECTIVE. The purpose of this study is to show the performance and evaluate the factors influencing the positivity rate (PR) of commercially produced 18F-fluciclovine PET/CT in the detection of recurrent prostate cancer in clinical practice. MATERIALS AND METHODS. We performed a retrospective cohort study of 152 men who had suspected biochemical recurrence of prostate cancer after receiving initial treatment and underwent fluciclovine PET/CT. PRs were calculated for whole-body, prostate and prostate bed, and extraprostatic locations. The influence of different factors, such as the absolute prostate-specific antigen (PSA) level, PSA kinetics, the Gleason score, and Gleason grade groups, on the PR was evaluated. RESULTS. The overall PR was 81% (123/152) for the whole body, 61% (92/152) for the prostate and prostate bed, and 55% (83/152) for extraprostatic locations. There was a linear increase in the PR with an increasing PSA level (p < 0.001). For the whole body, the PR for PSA levels of less than 1 ng/mL, 1 to less than 2 ng/mL, 2 to less than 5 ng/mL, and 5 or more ng/mL were 58% (32/55), 87% (13/15), 100% (39/39), and 92% (35/38), respectively. No statistically significant linear trend was found between the PR and the PSA level doubling time (p > 0.05). In addition, no statistically significant linear trend was found between the PR and increasing Gleason grade group. However, for every 1-unit increase in a patient's Gleason score, the odds of a positive finding in the extraprostatic location increased by 49% (p < 0.05). CONCLUSION. Commercially produced fluciclovine PET/CT has a high PR for detection of prostate cancer recurrence and is positively correlated with increasing PSA levels. For extraprostatic disease, the PR increases with higher Gleason scores.