Prostate Cancer Monitoring Using [18F]DCFPyL and Blood Based Biomarkers

Primary Objective: * To determine whether changes in uptake of \[18F\]DCFPyL PET/CT scans at baseline and after 6 weeks of treatment for metastatic castrate resistant prostate cancer, correlates with radiographic progression free survival (rPFS) as defined by Prostate Cancer Working Group 3 (PCWG3) criteria. Secondary Objectives: * To determine whether changes in uptake of \[18F\]DCFPyL PET/CT scans correlate with overall survival (OS) * To determine whether baseline SUVmax correlate with rPFS * To compare number of lesions detected with standard imaging at baseline and at the time of progression