Image-Guided Radiation Therapy, or IGRT, is the cutting edge in high-dose radiation for prostate cancer treatment, combining the advantages of IMRT with improved tacking 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.

An automated system for IGRT, the On-Board Imager, enables clinicians to obtain high-resolution three-dimensional images to pinpoint tumor sites, adjust patient positioning when necessary, and complete a treatment all within the standard treatment time slot.

With simple IMRT or proton beam therapy, radiation oncologists have had to deal with daily variations in patient positioning, including internal organ movement by treating a margin of healthy tissue around the tumor or by using other means, e.g. insertion and inflation of a rectal balloon, to stabilize and immobilize the prostate during treatment.

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.

We use a Clinac iX™ medical linear accelerator from Varian Medical Systems, for treating prostate cancer patients with Dynamic Targeting™ image-guided radiotherapy (IGRT). This robotic and automated technology combines a state-of-the-art treatment machine with sophisticated digital imaging, tracking and monitoring tools, enabling our doctors to deliver the most accurate treatments possible.