Abstract
Rationale: Characteristics and outcomes of lung cancer in patients with idiopathic pulmonary fibrosis (IPF) in the United States remain understudied.Objectives: To determine the tumor characteristics and survival of patients with IPF with non-small cell lung cancer (NSCLC) using U.S. population-based data.Methods: We selected Medicare beneficiaries from the Surveillance, Epidemiology, and End Results registry with histologically confirmed NSCLC diagnosed between 2007 and 2011. IPF was identified using two validated claims-based algorithms. We compared tumor characteristics and used logistic and Cox regression to compare rates of stage-appropriate therapy and of overall and lung cancer-specific survival in those with IPF and without IPF.Results: A total of 54,453 patients with NSCLC were included. Those with IPF were more likely to be diagnosed at an earlier stage (P < 0.01) and to have squamous histology (46% vs. 35%; P < 0.01) and lower-lobe tumors (38% vs. 28%; P < 0.01) than those without IPF. Patients with IPF and stages I-II disease had odds of receiving stage-appropriate therapy similar to patients without IPF who had stages I-II disease (odds ratio [OR], 1.13; 95% confidence interval [CI], 0.89-1.43); however, those with advanced disease were less likely to be treated (OR, 0.82; 95% CI, 0.68-0.99). Overall and lung cancer-specific survival were worse in patients with IPF (respectively, hazard ratio [HR], 1.35; 95% CI, 1.26-1.45; and HR, 1.21; 95% CI, 1.10-1.32).Conclusions: NSCLC has a unique presentation in patients with IPF and is associated with poorer prognosis. Further research is needed to identify optimal treatment strategies in this population.