This study will be assessing if the imaging probe 18-F Fluorocholine (18F-FCH) used during Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) scans, can better predict who will benefit from radiotherapy by identifying the source of cancer recurrence. This will be determined by measuring the number of men who have disease identified outside of the prostate bed (the small pocket or depression where the prostate used to be) on their 18F-FCH PET scan. Since F-18-FCH has been shown to be more sensitive in detecting prostate cancer that may have spread into lymph nodes or bone, it may potentially identify areas of prostate cancer spread not seen with standard imaging.