Impact of interstitial lung abnormalities on long-term mortality after resection for non–small cell lung cancer

Background Interstitial lung abnormalities (ILA) may overlap with subclinical interstitial lung disease (ILD). The 2025 American Thoracic Society (ATS) Clinical Statement revised the definition of ILA to better differentiate it from ILD. However, the prognostic significance of ATS-defined ILA after resection for non–small cell lung cancer (NSCLC) remains unclear. We aimed to investigate the impact of ATS-defined ILA on survival. Methods This study included patients who underwent curative-intent resection for NSCLC between 2011 and 2021. Preoperative computed tomography images were independently reviewed by two blinded observers and classified as ILA, non-ILA, or ILD according to the 2025 ATS Clinical Statement. Overall survival (OS), recurrence-free survival, cause of death, and postoperative complications were evaluated. Results Among the 1021 patients, 93 (9.1%) had ILA. In the multivariable Cox analysis, OS in patients with ILA was intermediate between that in non-ILA and ILD (HR vs. non-ILA, 1.88; p = 0.014; HR vs. ILD, 0.49; p < 0.001). Gray's test demonstrated higher 5-year cumulative incidences of lung cancer–specific death (0.24 vs. 0.10, p = 0.005) and respiratory-related death (0.15 vs. 0.02, p < 0.001) in the ILA group than in the non-ILA group. The incidence of postoperative complications was comparable between the groups (p = 0.56). After propensity score matching, the 5-year OS was lower in the ILA group (52.8% vs. 72.1%, p = 0.043). Conclusion ATS-defined ILA adversely affected long-term survival and escalated respiratory-related mortality after NSCLC resection. ILA may represent an intermediate prognostic phenotype between non-ILA and ILD. (250 words)