11. *Additional Inclusion Criteria - COHORT 1 (Patients Receiving Hemithoracic Radiation Therapy): *1. Patients must not have evidence of metastatic disease per PET/CT scan. Mediastinal lymph node involvement is acceptable. *2. Patients will have received at least 2 cycles of induction chemotherapy with pemetrexed/cisplatin or pemetrexed/carboplatin. *3. The following pulmonary function tests are required: a. Forced expiratory volume in 1 second (FEV1)>/=30% of predicted postoperative (ppoFEV1, as if patient underwent a pneumonectomy) based on the following formula using a quantitative perfusion scan: Predicted post-resection FEV1=FEV1 x % perfusion to the uninvolved lung from the quantitative perfusion report. b. Diffusing capacity of the lungs for carbon monoxide (DLCO)>35% predicted.