Androgen Receptor Signaling and Prostate-Specific Membrane Antigen Expression

This research study is a pilot study, and it is the first time investigators are directly examining the effect of standard androgen receptor antagonists on Prostate-Specific Membrane Antigen (PSMA) expression for participants with recurrent, asymptomatic, metastatic hormone-sensitive prostate cancer (mHSPC). This study will measure PSMA levels using standard PET/CT scans and participants will receive standard-of-care androgen receptor antagonist monotherapy. The research study procedures include screening for eligibility, study imaging and evaluations, blood collections, and follow up visits. The names of the treatment interventions involved in this study are: * Androgen receptor antagonist monotherapy. * PSMA PET/CT scan The U.S. Food and Drug Administration (FDA) has approved apalutamide, darolutamide, and enzalutamide for the treatment of prostate cancer. It is expected that about 15 people will take part in this research study. Participation in this research study is expected to last about 4 weeks. Funding for this research study is provided by a philanthropic gift.