Use of a single-scan Lung-RADS for pulmonary nodule assessment in resource-limited clinical settings.

Authors

Arshad S, Arshad A, Fatima M, Fatima Z, Nawaz H, Aziz Y, Zakir M, Tauqir J

Affiliations

• University Institute of Radiological Sciences and Medical Imaging Technology, Faculty of Allied Health Sciences, The University of Lahore, Lahore, Pakistan.
• Sahi Medical Center, Gujranwala, Pakistan.
• University Institute of Radiological Sciences and Medical Imaging Technology, Faculty of Allied Health Sciences, The University of Lahore, Lahore, Pakistan. Electronic address: zareen.fatima@rsmi.uol.edu.pk.
• Kot Khawaja Saeed Teaching Hospital, Lahore.

Abstract

BACKGROUND: Lung carcinoma remains the leading cause of cancer-related mortality worldwide, with a similar high burden in Asia. While Lung-RADS v2022 was developed to standardize lung cancer screening using low-dose CT (LDCT), its reliance on follow-up imaging limits feasibility in low-resource settings.

OBJECTIVE: To evaluate the diagnostic performance of Lung-RADS v2022 applied to a single baseline CT scan for pulmonary nodule characterization.

METHODOLOGY: Baseline CT scans from 79 participants in the National Lung Screening Trial (NLST) were reviewed by two radiologists using Lung-RADS v2022. Nodules were classified as benign (categories 1-3) or malignant (categories 4A-4X). Histopathological diagnosis or ≥2 years of CT stability was taken as the reference standard. Diagnostic performance was assessed using cross-tabulation, logistic regression, and ROC analysis.

RESULTS: The cohort comprised 45 men and 34 women (mean age: 62.9 years). Using single-scan Lung-RADS, sensitivity was 72% and specificity 90.7%, with overall accuracy of 84.8% and AUC of 0.79. Positive and negative predictive values were 78.3% and 87.5%, respectively. Chi-square analysis showed significant correlation between Lung-RADS categories and final diagnoses (p < 0.0001). The multivariate logistic regression model achieved sensitivity of 76.1%, specificity of 90.7%, and AUC of 0.92.

CONCLUSION: Lung-RADS retains diagnostic value when applied to baseline scans alone, though with reduced sensitivity compared to longitudinal use. Spiculated margins and size >7 mm were the most robust predictors of malignancy. These findings support the applicability of single-scan Lung-RADS in resource-limited settings lacking follow-up CT access.