Interstitial lung abnormalities in treatment-naïve advanced non-small-cell lung cancer patients are associated with shorter survival.

Objective: Interstitial lung diseases are associated with increased risk of lung cancer. The prevalence of ILA at diagnosis of advanced non-small-cell lung cancer (NSCLC) and its impact on overall survival (OS) remain to be investigated.

Materials And Method: The study included 120 treatment-naïve stage IV NSCLC patients (53 males, 67 females). ILA was scored on CT prior to any systemic therapy using a 4-point scale [0=no evidence of ILA, 1=equivocal for ILA, 2=suspicious for ILA, 3=ILA] by a sequential reading method previously reported. ILA scores of 2 or 3 indicated the presence of ILA.

Results: ILA was present in 17 patients (14%) with advanced NSCLC prior to any treatment (score3: n=2, score2: n=15). These 17 patients were significantly older (median age: 69 vs. 63, p=0.04) and had a heavier smoking history (median: 40 vs. 15.5 pack-year, p=0.003) than those with ILA score 0 or 1. Higher ILA scores were associated with shorter OS (p=0.001). Median OS of the 17 patients with ILA was 7.2 months [95%CI: 2.9-9.4] compared to 14.8 months [95%CI: 11.1-18.4] in patients with ILA score 0 or 1 (p=0.002). In a multivariate model, the presence of ILA remained significant for increased risk for death (HR=2.09, p=0.028) after adjusting for first-line systemic therapy (chemotherapy, p<0.001; TKI, p<0.001; each compared to no therapy) and pack years of smoking (p=0.40).

Conclusion: Radiographic ILA was present in 14% of treatment-naïve advanced NSCLC patients. Higher ILA scores were associated with shorter OS, indicating that ILA could be a marker of shorter survival in advanced NSCLC.