Prospective Monitoring of Subjects With Biochemically Recurrent Prostate Cancer Using 18FDCFPyL

Background: Prostate cancer is the second leading cause of cancer-related death in American men. The disease recurs in up to 50,000 men each year after their early-stage disease was treated; however, at this stage, imaging scans are often unable to find the disease in the body. In this natural history study, researchers want to find out if a new radiotracer (18F-DCFPyL) injected before positron emission tomography (PET) imaging can help identify sites in the body with cancer. Objective: To learn more about how 18F-DCFPyL PET/CT scans detect change over time in men with recurrent prostate cancer. Eligibility: Men aged 18 and older with prostate cancer that returned after treatment. Design: Participants will be screened with blood tests. They will also have a bone scan and a computed tomography (CT) scans of the chest, abdomen, and pelvis. Participants will have an initial study visit. They will have a physical exam and blood tests. They will have a PET/CT scan with 18F-DCFPyL. The radiotracer will be injected into a vein; this will take about 20 seconds. The PET/CT scan will be done 1 to 2 hours later. Participants will lie still on a scanner table while a machine captures images of their body. The scan will take 45 minutes. Participants will return for blood tests every 3 months. Participants will return for additional scans with 18F-DCFPyL on this schedule: Once a year if their previous scan was negative for prostate cancer. Every 6 months if their previous scan was positive for prostate cancer. Participants may be in the study up to 5 years.

* INCLUSION CRITERIA: * History of primary treatment for prostate cancer (either surgery or radiation) * Serum PSA \>= 0.50 * Serum testosterone \>100 * Age \>=18 years * Men must agree to use highly effective contraception (surgical sterilization) for 7 days after every study agent administration. Note: abstinence, defined as no heterosexual sexual intercourse when this is in line with the preferred and usual lifestyle of the subject is also acceptable * The ability of a participant to understand and the willingness to sign a written informed consent document EXCLUSION CRITERIA: -Evidence of soft tissue disease on CT scan (or magnetic resonance imaging \[MRI\] as clinically indicated). NOTE: Lymph nodes \