Controlling nutritional status predicts postoperative survival and acute exacerbation in resected non-small cell lung cancer with interstitial lung disease

Background: Several immune-nutritional markers have been reported as convenient prognostic factors in malignancies, including lung cancer. The controlling nutritional status (CONUT) score has been reported as a prognostic factor in patients with resected lung cancer. However, its significance in resected cases of lung cancer complicated by interstitial lung disease (ILD) has not been previously reported. Methods: This study included 120 patients with non-small cell lung cancer complicated by ILD who underwent lung resection at our department between 2010 and 2019. Based on the CONUT score, patients were classified into three groups: normal (0-1 points), mildly undernourished (2-4 points), and moderately undernourished (5-8 points). Results: The median age of patients was 73 years, and 86.7 % were male. ILD imaging patterns were categorized as usual interstitial pneumonia (UIP), probable UIP, or indeterminate UIP in 21.7 %, 62.5 %, and 15.8 % of cases, respectively. Postoperative acute exacerbation (AE) occurred in 16 patients (13.7 %), with eight deaths attributable to AE. Among the nutritional groups, AE-ILD incidence was 9 %, 16 %, and 33 % in the normal, mildly undernourished, and moderately undernourished groups. Logistic regression analysis identified the CONUT score as an independent risk factor for AE, alongside other factors such as sex, surgical technique, imaging findings, history of ILD exacerbation, steroid use, Krebs von den Lungen-6 levels, and predicted vital capacity. Conclusions: The CONUT score emerged as a significant prognostic factor and an independent risk factor for AE in patients with resected lung cancer complicated by ILD.