The investigators hypothesize that MRI based adaptive planning will provide a novel method to dose escalate safely with acceptable organ at risk doses. In addition, further improvements in radiotherapy targeting accuracy, normal tissue avoidance, and conformality of target-tissue coverage will be achieved through the use of 4D real-time tracking which is derived by deformably registering daily MR and planning MR (MRsim) and Computed Tomography Simulator (CTsim) with advanced non-rigid image-registration tools.