Impact of idiopathic pulmonary fibrosis on advanced non-small cell lung cancer survival

The clinical features of patients with advanced non-small cell lung cancer (NSCLC) and interstitial lung disease (ILD) have not fully been elucidated. This study aimed to investigate the clinical features of these patients, particularly with idiopathic pulmonary fibrosis (IPF). Data on 218 patients with pathologically confirmed diagnoses of NSCLC who had been treated with chemotherapy and/or molecular targeted therapy were retrospectively analyzed for progression-free survival (PFS), overall survival (OS), responses to first-line therapy, and incidence of acute exacerbations (AEs). Fifty-three of the 218 patients were diagnosed with ILD, and 34 of them with IPF. The frequency of epidermal growth factor receptor (EGFR) mutation was significantly lower in ILD and IPF patients than in non-ILD patients (2 or 0 vs. 32 %, respectively). Median PFS and OS were significantly shorter in both ILD and IPF patients than in non-ILD patients (118, 92, and 196 days for PFS, and 267, 223, and 539 days for OS, respectively). Multivariate analysis showed that poor performance status, absence of EGFR mutation, and presence of IPF were poor prognostic factors for PFS and OS. Disease control rate (DCR) was significantly lower in ILD and IPF patients than in non-ILD patients regardless of the presence of EGFR mutation (67 or 53 vs. 85 %, respectively). The incidence of AEs of ILD was significantly higher during chemotherapy with docetaxel-containing regimens (seven of 38; 18.4 %). Both IPF and ILD were associated with lower EGFR positivity, lower DCR, and shorter PFS and OS in advanced NSCLC patients.