- The participant will be required to have fiducial markers placed within the prostate as part of this study. These are very small gold markers that are placed in the prostate. This procedure is similar to the biopsy that the participant had to diagnose their cancer. This procedure is routinely performed to permit imaging and position corrections to improve the precision of the external beam (radiation) delivery (Image Guided Radiation Therapy). The placement of the three gold markers is performed by an Urologist. The fiducials are placed under ultrasound guidance. This is also considered standard of care and is not experimental.