Computed tomography on lung cancer screening is useful for adjuvant comorbidity diagnosis in developing countries.

Purpose: The aim of this study was to analyse and quantify the prevalence of six comorbidities from lung cancer screening (LCS) on computed tomography (CT) scans of patients from developing countries. Methods: For this retrospective study, low-dose CT scans (n=775) were examined from patients who underwent LCS in a tertiary hospital between 2016 and 2020. An age- and sex-matched control group was obtained for comparison (n=370). Using the software, coronary artery calcification (CAC), the skeletal muscle area, interstitial lung abnormalities, emphysema, osteoporosis and hepatic steatosis were accessed. Clinical characteristics of each participant were identified. A t-test and Chi-squared test were used to examine differences between these values. Interclass correlation coefficients (ICCs) and interobserver agreement (assessed by calculating kappa coefficients) were calculated to assess the correlation of measures interpreted by two observers. p-values <0.05 were considered significant. Results: One or more comorbidities were identified in 86.6% of the patients and in 40% of the controls. The most prevalent comorbidity was osteoporosis, present in 44.2% of patients and in 24.8% of controls. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46% of cases, respectively. The kappa coefficient for CAC was 0.906 (p<0.001). ICCs for measures of liver, spleen and bone density were 0.88, 0.93 and 0.96, respectively (p<0.001). Conclusions: CT data acquired during LCS led to the identification of previously undiagnosed comorbidities. The LCS is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatment.

Chest MRI with CT in the assessment of interstitial lung disease progression in patients with systemic sclerosis.

OBJECTIVE: To describe the performance of CT and MRI in the assessment of the progression of interstitial lung disease (ILD) associated with SSc and demonstrate the correlations of MRI with pulmonary function test (PFT) and CT scores. METHODS: This prospective single-centre observational study included patients with SSc diagnoses, and magnetic resonance (MR) images were assessed visually using the Scleroderma Lung Study (SLS) I system. Differences in the median scores were assessed with Student's t-test and the Wilcoxon rank-sum test. Pearson's and Spearman's rank correlation coefficients were calculated to correlate imaging scores and PFT results. Using disease progression as the gold standard, we calculated the area under the curve (AUC) of the CT and MRI scores with Harrel's c-index. The best thresholds for the prediction of disease progression were determined by receiver operating characteristic curve analysis with maximum Youden's Index (P < 0.05). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the scores were calculated. RESULTS: The AUCs for MRI and CT scores were 0.86 (0.72-0.98; P = 0.04) and 0.83 (0.70-0.99; P = 0.05), respectively. CT and MRI scores correlated with Forced vital capacity (%FVC) (MRI: r = -0.54, P = 0.0045; CT: r = -0.44; P = 0.137) and diffusing capacity of the lung for carbon monoxide (MRI: r = -0.39, P = 0.007; CT r = -0.36, P = 0.006). The sensitivity, specificity, PPV and NPV were 85%, 87.5%, 88.34% and 86.11% (MRI score) and 84.21%, 82.35%, 84.14% and 82.4% (CT score), respectively. CONCLUSIONS: MRI scores from patients with SSc may be an alternative modality for the assessment of ILD progression in patients with SSc.