Prior radiation therapy to the chest [Period ] Patients with N or N nodal disease or T primary disease must undergo liver and bone imaging (as described in .. and ..) within days prior to randomization, irrespective of baseline lab results, and studies must not demonstrate metastatic disease. Chest imaging with chest x-ray PA and Lateral, CT of the chest, or PET-CT must also be performed. Patients with any anginal chest pain; defined by a known diagnosis of angina; or defined by chest pressure, squeezing, radiating pain to arms, shoulders, or neck from the chest; with or without exertion Prior radiation therapy to the chest, neck or axilla Known history of current or recent clinical diagnosis of tuberculosis (within months prior to enrollment). A chest x-ray (XR) will be performed to screen for active tuberculosis (TB) for patients who have a history of treated TB. A chest XR will be performed in all patients to screen for active TB unless there has been a prior chest XR or computed tomography (CT) scan of chest within month of entry Subjects receiving consolidative chest radiation Patients must have pretreatment neck and chest imaging Prior radiation to chest or abdomen, or to > % of the marrow cavity Patients who have previously received therapeutic radiation therapy to the chest Patients who have previously received therapeutic radiation therapy to the chest Prior breast or chest radiotherapy for any indication Participants who have received prior chest radiation are excluded Chest x-ray negative for metastatic disease Prior history of radiation to the chest Prior radiation therapy for esophageal cancer or prior chest radiotherapy Chest radiograph Patients must not have received prior chest radiation therapy for NSCLC Chest radiation ? weeks prior to first dose History of prior chest radiation therapy Prior radiation to the chest or abdomen Metastatic disease or regional lymph node involvement. Chest CT will be mandatory prior to enrollment to evaluate for the presence of metastatic disease. Pulmonary nodule(s) < mm without a histological diagnosis may not be the basis for study exclusion given the lack of specificity of chest CT. If pulmonary nodule(s) > mm are noted on chest CT but appear stable relative to prior chest imaging of at least months duration, then this is permitted. No prior radiation therapy to the chest, breast or supraclavicular fossa that would limit radiation delivery to the full prescription dose Patients who have previously received radiation therapy to the chest or abdomen such that there would be overlap between the previous and current radiation field Patients must have received prior radiation treatment to the chest; records of prior radiation treatment must be available Patients who have never received radiation to the chest Patients who received radiation to the chest within the past months (in a region that overlaps with current radiation fields) History of radiation therapy to the chest Subject has acute chest syndrome Chest X-ray within month of registration Subject has had chest compressions as part of CPR No prior radiation therapy to the chest, neck or axilla Previous radiation to the chest or breast Were treated with ? Gy of chest radiation therapy (RT) (recent revision with a lower dose threshold) Have an interval from their chest RT to the time of enrollment of at least years Prior chest radiation or radiation for esophageal cancer Subjects who have been treated with radiation therapy on the chest Any history of radiotherapy to the chest prior to systemic therapy or planned consolidation chest radiation therapy (except paliative care outside of the chest). Patients who received radiation to the chest within the past months