Abstract
Lung transplant recipients have an increased risk of lung cancer that is poorly understood. Prior studies are largely descriptive and single-center, and have not examined risk factors or outcomes in this population. This registry-linkage study utilized matched transplant and cancer registry data from 17 US states/regions during 1987-2012. We used standardized incidence ratios (SIRs) to compare incidence with the general population, Poisson models to identify lung cancer risk factors, and Cox models to compare survival after diagnosis. Lung cancer risk was increased among lung recipients (SIR 4.8, 95% confidence interval [CI] 4.1-5.5). Those with single lung transplant had 13-fold (95% CI 11-15) increased risk in the native lung. Native lung cancer risk factors included age, prior smoking, time since transplant, and idiopathic pulmonary fibrosis. Compared with cases in the general population, lung cancers in recipients were more frequently localized stage (P = .02) and treated surgically (P = .05). However, recipients had higher all-cause (adjusted hazard ratio 1.90, 95% CI 1.52-2.37) and cancer-specific mortality (adjusted hazard ratio 1.67, 95% CI 1.28-2.18). In conclusion, lung cancer risk is increased after lung transplant, especially in the native lung of single lung recipients. Traditional risk factors are associated with lung cancer in these patients. Lung cancer survival is worse among lung recipients despite earlier diagnosis.