CT Simulation
ProcedurePatient will undergo routine CT simulation to initiate radiation treatment planning process. For the purposes of this study, the day of CT simulation "mapping scan" will be counted as day 0. After the patient completes the CT simulation scan, the CT images and plan/structure files will be sent to the treatment planning system. The treating physician will contour the gross tumor volume (GTV) including the involved primary lung tumor and/or the involved lymph nodes.