PT - JOURNAL ARTICLE AU - Olayinka Abiodun-Ojo AU - Ashesh Jani AU - Akinyemi Akintayo AU - Mehrdad Alemozaffar AU - Oladunni Akin-Akintayo AU - Oluwaseun Odewole AU - Funmialyo Tade AU - Peter Nieh AU - Viraj Master AU - Pretesh Patel AU - Joseph Shelton AU - Omer Kucuk AU - Zhengjia Chen AU - Bruce Hershatter AU - Bridget Fielder AU - Raghuveer Halkar AU - David Schuster TI - <strong>[<sup>18</sup>F]-fluciclovine positivity rate is not affected by androgen deprivation therapy (ADT) in recurrent prostate cancer post-prostatectomy.</strong> DP - 2019 May 01 TA - Journal of Nuclear Medicine PG - 1576--1576 VI - 60 IP - supplement 1 4099 - http://jnm.snmjournals.org/content/60/supplement_1/1576.short 4100 - http://jnm.snmjournals.org/content/60/supplement_1/1576.full SO - J Nucl Med2019 May 01; 60 AB - 1576Objectives: [18F]-fluciclovine is a synthetic amino acid PET radiotracer with utility in recurrent prostate cancer detection. We examined the effect of ADT on recurrent prostate cancer detection in post-prostatectomy patients with detectable serum prostate-specific antigen (PSA). Methods: One hundred and sixty-two patients were enrolled in a randomized, prospective intention-to-treat clinical trial for potential salvage radiotherapy for recurrent prostate cancer post-prostatectomy. Seventy-seven of these patients underwent fluciclovine PET-CT prior to radiotherapy. Prostate bed, pelvis and extrapelvic uptake of fluciclovine were noted. Patients “on ADT” had either luteinizing hormone-releasing hormone (LHRH) agonist or testosterone receptor antagonist initiated any time before the fluciclovine scan was performed. ADT-naïve patients had no ADT prior to the fluciclovine scan. Fluciclovine positivity rates were compared between patients on ADT and ADT-naïve patients. Descriptive statistics were reported and statistical significance of difference was determined using two-sample t-test and Fisher’s exact test. Results: 12/77 (15.6%) patients were on ADT at the time of the scan. Average (±SD) time interval between start of ADT and PET-CT scan was 43.7 (±29.6) days. PSA values were not significantly different between patients on ADT and ADT-naïve patients (2.39 (±2.59) ng/ml vs. 1.65 (±4.38) ng/ml; p=0.57). Median (range) Gleason score was 8 (7-9) in the ADT group and 7 (6-9) in the non-ADT group. Overall, fluciclovine positivity rates were similar in the ADT group 10/12 (83.3%) compared to the non-ADT group 51/65 (78.5%) (p=1.00). Positivity rates increased with PSA in both the ADT group (71.4% at PSA &lt;2 ng/ml and 100% at PSA ≥2ng/ml) and the ADT-naïve group (75% at PSA &lt;2 ng/ml and 100% at PSA levels ≥2 ng/ml). Differences in positivity across PSA levels were not statistically significant (p=1.00). There was no difference in fluciclovine distribution of activity (prostate bed, pelvic and extrapelvic uptake) between ADT and ADT naive groups (p=1.00) (see table). Conclusions: Fluciclovine PET-CT can detect prostate cancer recurrence in patients on ADT, with similar positivity rates to ADT-naive patients. A potential reason for this finding is that fluciclovine uptake is mediated by amino acid transporters and is not directly related to testosterone receptor status.