Lung Transplant Recipients at Higher Risk for Lung Cancer Than General Population

A recent analysis of the Transplant Cancer Match (TCM) Study underscores how the risk for lung cancer is increased in recipients of lung transplants compared with individuals in the general public (Am J Transplant. 2018 Dec 18. Epub ahead of print).

“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,” said Matthew A. Triplette, MD, MPH, Assistant Professor, Department of Medicine, University of Washington, Seattle, and colleagues.

Using data from the National Cancer Institute's longitudinal TCM study of approximately 9000 first-time recipients of lung transplants between 1987 and 2012, the investigators conducted an analysis to identify risk factors and outcomes in this population. They compared the incidence of lung cancer between lung transplant recipients and the general population using standardized incidence ratios (SIRs) and used Poisson and Cox models to identify risk factors for lung cancer and compare postdiagnosis survival outcomes.

Ultimately, Dr Triplette and colleagues found that the risk for lung cancer was increased among recipients of lung transplants (SIR, 4.8; 95% confidence interval [CI], 4.1‐5.5). There were 183 lung cancer cases reported during follow-up (528 per 100,000 person-years), and the median time from transplant to cancer was 3.9 years, regardless of whether the disease originated in a native or donor lung.

A 13-fold increased risk for lung cancer in the native lung was identified in recipients of single-lung transplants, and risk factors for native lung cancer included age, smoking history, time since transplant, and idiopathic pulmonary fibrosis.

Of note, lung cancer cases in transplant recipients were more likely to be localized stage (P = .02) and treated surgically (P = .05) than cases in the general population, and were also tied to 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,” Dr Triplette and colleagues said.

“Traditional risk factors are associated with lung cancer in these patients. Lung cancer survival is worse among lung recipients despite earlier diagnosis,” they added.—Hina Khaliq