Lung transplantation confers an increased risk of lung cancer, especially for single lung transplant recipients, due to both the epidemiologic risk factors associated with the patient population and the posttransplantation immunosuppression required. We report what we believe to be the first case of combined small cell lung carcinoma identified in the native lung of a single lung transplant recipient. Combined small cell lung cancer is an increasingly recognized subtype of small cell carcinoma, and its possible presence is an important consideration in the interpretation of fine-needle aspiration biopsies. In our case, initial fine-needle aspiration suggested squamous cell carcinoma, and it was only after lobectomy that the diagnosis of small cell carcinoma was made. The case highlights the increased risk of malignancy in lung transplant recipients and suggests a role for adaptation of lung cancer screening guidelines to address this high-risk population.