RecruitingPhase 2Drug trialPET Scan Study to Detect Prostate Cancer in Patients with Early PSA RecurrenceFlotufolastat F-18, sold under the brand name Posluma, is a radioactive diagnostic agent for use with positron emission tomography (PET) imaging for prostate cancer. The research is being done to study the capability of 18F-rhPSMA-7.3 (flotufolastat F-18) PET scan to detect prostate cancer when there are very low levels of Prostate-Specific Antigen (PSA) following previous radical prostatectomy surgery.