The aims of this study were to report on our initial experience using 18F-fluciclovine PET/CT to detect recurrent prostate carcinoma in patients with low serum prostate-specific antigen (PSA) after definitive treatment of primary disease and to conduct a preliminary investigation for factors associated with positive scan findings.
In this retrospective study, 18F-fluciclovine PET/CT scans from 28 men with suspected recurrence of prostate carcinoma and PSA values of 1 ng/mL or less were examined to identify the site(s) of disease recurrence. Differences in detection rate for Gleason scores of 7 and greater than 7, T2 and T3 disease, negative and positive surgical margins, and negative and positive seminal vesicle invasion were compared using the Fisher exact test. Mean PSA and mean PSA doubling time of patients with positive scans and negative scans were compared using the independent 2-group t test.
At least one site of disease recurrence was identified in 13 (46.4%) of 28 patients. Disease detection rate was significantly higher in patients with history of Gleason score greater than 7 (Fisher exact test, P = 0.004). Mean PSA and PSA doubling time were not significantly different between patients with positive and negative 18F-fluciclovine PET/CT scans (P = 0.29 and 0.70, respectively).
Detection of recurrent prostate cancer using 18F-fluciclovine PET/CT is possible in patients with low but rising PSA levels of 1 ng/mL or less. In such patients, local and nodal recurrences are more common than distant metastasis, and Gleason score greater than 7 is associated with positive scan results.
From the Departments of *Radiology, and
†Radiation Oncology, Keck School of Medicine, University of Southern California, Los Angeles, CA.
Received for publication October 18, 2018; revision accepted November 8, 2018.
Conflicts of interest and sources of funding: Hossein Jadvar was supported by the National Institutes of Health grant numbers R21-EB017568 and P30-CA014089. The rest of the authors declare no potential conflicts of interest.
Correspondence to: Hossein Jadvar, MD, PhD, MPH, MBA, Department of Radiology, University of Southern California, 2250 Alcazar St, CSC102, Los Angeles, CA 90033. E-mail: firstname.lastname@example.org.