RecruitingEarly Phase 1ProcedurerhPSMA-73 PET-MRI Imaging for the Detection of Prostate Cancer Among Men Who Are Otherwise Candidates for Active SurveillanceThis clinical trial evaluates whether positron emission tomography-magnetic resonance imaging (PET-MRI) using the radioactive drug radiohybrid prostate-specific membrane antigen (rhPSMA)-7.3 may help in detecting higher grade or stage disease in men with low and favorable intermediate risk prostate cancer who are candidates for active surveillance. A PET scan is a test that uses a radioactive drug and a computer to create images of how organs and tissues in the body are functioning. The radioactive drug used in this study, rhPSMA-7.3, attaches to the abnormal cells in the body at a different rate than normal cells which allows the scanner to create a detailed picture of how the body is working. An MRI scan uses strong magnets and computers to create detailed images of the soft tissue in your body. A multiparametric (mp)MRI is a type of MRI scan that creates a more detailed picture of the prostate gland. Using rhPSMA-73 with PET-MRI and mpMRI may be more effective in detecting higher grade or stage disease in men with low and favorable intermediate risk prostate cancer.