Chest radiotherapy is a mainstay of management of thoracic oncology patients. Radiotherapy also injures nontarget tissues such as the lungs, coronary arteries, and esophagus, and safe limits to the doses that can be delivered to tumors have been determined empirically. Patients afflicted with lung cancer due to smoking often have concomitant chronic obstructive pulmonary disease which, on occasion, manifests as bullous emphysema. We describe a case and course of treatment of lung cancer found incidentally in a patient followed for severe pulmonary emphysema. Treatment consisted of radiochemotherapy after induction chemotherapy. Three years after the end of antineoplastic treatment, a follow-up computed tomography scan revealed complete retraction of a large emphysematous bulla that had been present prior to treatment.