Current dose escalation regimens with and without chemotherapy have failed to achieve improved local control and overall survival over standard of care therapy to date. Difficulties with dose escalation have been largely due to dose limiting toxicities of surrounding normal organs, in particular to the normal lung parenchyma, and esophagus. Real time, online adaptive planning using magnetic resonance imaging (MRI) could achieve significant volume reduction of primary lung disease over the course of therapy, thereby reducing dose to normal structures, and providing a mechanism in which to dose escalate safely, and more effectively with accurate target delineation.