Fibrotic Interstitial Lung Abnormalities on Preoperative CT Images Predict Cause-Specific Mortality after Stage I Non-Small Cell Lung Cancer Resection.

Abstract

Interstitial lung abnormalities (ILAs) and preclinical interstitial lung disease (ILD) are associated with an increased incidence of lung cancer and high mortality. However, their impact on cause-specific mortality following surgical resection of clinical stage I non-small-cell lung cancer (NSCLC) remains unclear. We evaluated the relationship between preoperative ILAs and postoperative mortality in patients with clinical stage I NSCLC who underwent surgical resection. In this retrospective study, we included patients who underwent complete resection for clinical stage I NSCLC between 2006 and 2018 and excluded those with ILD. Preoperative computed tomography (CT) images were classified as no ILA, non-fibrotic ILA, or fibrotic ILA. Of the 704 included patients, 75 (10.6%) had ILAs, including 24 (3.4%) with non-fibrotic ILA and 51 (7.2%) with fibrotic ILA. Patients with fibrotic ILAs were older (median age, 75 years) and predominantly male (88.2%), whereas 629 patients had no ILA (median age, 69 years; male, 49.1%). The 5-year overall survival rates were 90.0%, 71.0%, and 35.1% in patients with no, non-fibrotic, and fibrotic ILAs, respectively (log-rank p < 0.001). Fibrotic ILAs were independently associated with poorer overall survival (hazard ratio [HR] 4.50; 95% confidence interval [CI] 2.86-7.09) and higher mortality (lung cancer-specific: HR 7.64; 95% CI 4.03-14.46; other cause: HR 2.79; 95% CI 1.44-5.42) than no ILAs. Fibrotic ILAs were associated with increased lung cancer-specific and other-cause mortality after resection for stage I NSCLC, suggesting that fibrotic ILAs, although often subtle on routine CT, may serve as clinically meaningful imaging prognostic markers.