PSMA-based 18F-DCFPyL PET/CT and PET/MRI Pilot Studies in Prostate Cancer

The investigators propose to evaluate a novel second-generation low-molecular-weight prostate specific membrane antigen (PSMA)-based positron emission tomography (PET) agent, 18F-DCFPyL, for detection of primary and metastatic prostate cancer. 18F-DCFPyL PET demonstrates very high tumor-to-background and tumor specific uptake which may allow for a more sensitive and accurate method for detection of early tumor recurrence and metastatic disease as compared to current PET radiotracers and current standard-of-care imaging including 99mTc-methylene diphosphonate bone scintigraphy (bone scan), contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Primary Objectives: The investigators propose to evaluate this PET agent for four different prostate cancer clinical scenarios. 1. detection of clinically significant high-grade prostate cancer and initial staging 2. detection of sites of recurrence in the setting of biochemical recurrence after definitive prostatectomy 3. detection of advanced androgen-resistant metastatic prostate cancer, and 4. detection of clinically significant prostate cancer in very low to intermediate risk primary prostate cancer Secondary Objectives: * Evaluate the performance of 18F-DCFPyL PET and MRI whole body DWI for detection of local-nodal and distant metastatic disease on initial staging compared to conventional imaging modalities (CT and bone scintigraphy). * Correlate 18F-DCFPyL PET standardized-uptake values (SUV) and MRI parameters with PSMA expression by prostatectomy pathology IHC. * Evaluate the specificity of 18F-DCFPyL PET for differentiating primary prostate cancer versus non-malignant prostate lesions (BPH, prostatitis). * Comparison of whole body low-dose CT and whole body MRI derived PET SUV-quantitation. * Evaluate the performance of dedicated pelvic 18F-DCFPyL PET/MRI with dynamic PET acquisition and multi-parametric MRI for differentiation of urine versus recurrent malignancy in the prostatectomy bed. * Evaluate the contribution of whole body MRI DWI obtained from PET/MRI to improve the diagnostic performance of 18F-DCFPyL PET/CT and PET/MRI for metastatic prostate cancer lesion detection. * Assess the quantitative accuracy of PET-derived standardized uptake value (SUV)-based parameters in 18F-DCFPyL PET obtained from PET/MRI versus PET/CT. * Assess the quantitative reproducibility of 18F-DCFPyL PET/CT derived-SUV values in normal organ and metastatic tumor lesions. * Evaluate the ability of 18F-DCFPyL PET to improve detection of clinically significant primary prostate cancer in men with very low to intermediate risk prostate cancer under active surveillance or watchful waiting. Update: As of July 2022 verification, the investigators are no longer enrolling into sub-studies 1 and 2.