Inclusion Criteria:  Disease that is being treated as locally advanced non-small cell lung cancer (NSCLC) or limited stage small cell lung cancer (SCLC). Specifically, AJCC 8th edition staging with T3 or T4 and/or N1-3 disease. Patients with unclear pathology who are being treated clinically as non-small cell lung cancer or as limited stage small cell lung cancer are eligible. Plan for radiotherapy to be delivered with curative intent per the treating radiation oncologist in the Wake Forest Baptist Comprehensive Cancer Center Department of Radiation Oncology.  Exclusion Criteria: Not being treated with radiation, or being treated with non-curative intent per the treating radiation oncologist.