Prostate MRI and Pylarify PSMA PET/CT

The goal of the study is to better understand how an individual tumor responds to radiation therapy and determine if advanced imaging can be used for prognostic purposes, especially to predict areas of local resistance and failure. The study population are patients with high risk prostate malignancy treated with a combination of external beam radiation therapy (EBRT)/brachytherapy (BT) and androgen deprivation therapy (ADT). Patients enrolled in this trial will undergo a pre-treatment MRI and PSMA PET/CT prior to the initiation of ADT and the first EBRT fraction, a mid-treatment MRI and PSMA PET/CT prior to second brachytherapy fraction, and a third MRI and PSMA PET/CT will be performed after 75% testosterone recovery or 12 months post-ADT (whichever comes first). The pre-treatment MRI and PSMA PET/CT is part of standard of care for prostate cancer workup, however all additional MRI and PSMA PET/CT mid-treatment or after treatment completion are additional research scans.