IMRT
Dr. Peterson explains, in radiation therapy it is often very important to give a high dose of radiation to a tumor while minimizing the amount of normal tissue that is affected by that radiation. The reason for this is that it often takes a high dose of radiation therapy to eradicate a tumor but the amount of normal tissue that receives high doses of radiation must be kept low in order to minimize the risk of radiation therapy side effects.
Since IMRT wraps radiation doses tightly around the tumor it allows for more precise treatment while sparing the surrounding normal tissue. This leads to better cancer control rates and often to lower rates of significant radiation therapy side effects.