Gallium Ga 68-labeled PSMA-11 PET/CT and Fluciclovine F18 PET/CT in Imaging Participants With Recurrent Prostate Cancer After Surgery

PRIMARY OBJECTIVES: I. To compare the detection rates of gallium 68-labeled PSMA-11 (\[68\]Ga-PSMA-11) PET/CT and fluciclovine F18 (Axumin) PET/CT for the identification of tumor location(s), by patient and region based analysis. SECONDARY OBJECTIVES: I. Detection rate on a per-patient basis of (68)Ga-PSMA-11 PET/CT and Axumin PET/CT, stratified by prostate-specific antigen (PSA) value (0.2 - \< 0.5; 0.5 - \< 1.0; 1.0 - \< 2.0). II. Sensitivity and positive predictive value (PPV) on a per-patient basis, of (68)Ga-PSMA-11 PET/CT and Axumin PET/CT for the detection of tumor location(s), confirmed by histopathology/biopsy and/or clinical and conventional imaging follow-up. III. Agreement among the readers, separate for (68)Ga-PSMA-11 PET/CT versus Axumin PET/CT. OUTLINE: Participants receive (68)Ga-PSMA-11 intravenously (IV) and 60-90 minutes later, undergo PET/CT imaging over 3 hours. Participants also undergo best standard of care Axumin PET/CT within 2 weeks before or after (68)Ga-PSMA-11 PET/CT. After completion of the PET/CT scan, participants are followed up between 1 and 3 days and up to 12 months.