the advantages of Intensity Modulated Radiation Therapy, or IMRT, with improved tracking and targeting of the therapy to the prostate in order to maximize the dose to the prostate while minimizing radiation to the rectum and bladder which can be the cause of side effects.
IGRT enables doctors to locate the tumor before each dose is administered by locking on to three gold “markers” inserted into the prostate while the patient is in the treatment position prior to treatment planning. Even if the prostate moves, as it often does even with the simple act of breathing or rectal fullness, the IGRT adjusts daily to any new position. Thus the “safety” margin of radiation around the prostate can be minimized from several centimeters down to just millimeters. Furthermore, the higher dosage of radiation to the prostate that can be achieved with IGRT has been shown to improve the long term cure rate of prostate cancer, compared to techniques that deliver a lower dosage.