Association between Mortality and Lung Low Attenuation Areas in NSCLC Treated by Surgery

Background: to test the association with overall survival (OS) of low attenuation areas (LAAs) quantified by staging computed tomography (CT) of patients who underwent radical surgery for nonsmall-cell lung cancer (NSCLC). Methods: patients who underwent radical surgery for NSCLC at our institution between 1 January 2017 and 30 November 2021 were retrospectively evaluated. Patients who performed staging or follow-up CTs in other institutions, who received lung radiotherapy or chemotherapy, and who underwent previous lung surgery were excluded. At staging and 12-months follow-up CT, LAAs defined as voxels <−950 Hounsfield units, were extracted by software. The percent of LAAs relative to whole-lung volume (%LAAs) and the ratio between LAAs in the lobe to resect and whole-lung LAAs (%LAAs lobe ratio) were calculated. Cox proportional hazards regression analysis was used to test the association between OS and LAAs. Results: the final sample included 75 patients (median age 70 years, IQR 63–75 years; females 29/75, 39%). It identified a significant association with OS for pathological stage III (HR, 6.50; 95%CI, 1.11–37.92; p = 0.038), staging CT %LAAs ≥ 5% (HR, 7.27; 95%CI, 1.60–32.96; p = 0.010), and staging CT %LAA lobe ratio > 10% (HR, 0.24; 95%CI 0.05–0.94; p = 0.046). Conclusions: in patients with NSCLC who underwent radical surgery, a %LAAs ≥ 5% and a %LAA lobe ratio > 10% at staging CT are predictors, respectively, of shorter and longer OS. The LAA ratio to the whole lung at staging CT could be a critical factor to predict the overall survival of the NSCLC patients treated by surgery.