Performance of the Vancouver Risk Calculator Compared with Lung-RADS in an Urban, Diverse Clinical Lung Cancer Screening Cohort.

PURPOSE: To compare the performance of the Vancouver risk calculator (VRC) with the American College of Radiology's Lung CT Screening Reporting and Data System (Lung-RADS) for a lung cancer screening cohort in an urban, diverse clinical setting.

MATERIALS AND

METHODS

This study included a total of 486 patients with lung nodules (63 years ± 5.2 [standard deviation], 261 female patients), 448 of whom had lung nodules that were subsequently classified as benign and 38 of whom had those that were classified as malignant. The mean follow-up time was 40.0 months ± 14. Institutional review board approval was obtained for this Health Insurance Portability and Accountability Act-compliant retrospective study, and a waiver of informed consent was received. All patients undergoing lung cancer screening who underwent an initial baseline screening CT between December 2012 and June 2016 that demonstrated a nodule and had at least 1 year of follow-up comprised the study population. Each examination was assigned a Lung-RADS score between 2 and 4B, with 4A and 4B considered as showing positive results. The VRC calculates the risk of cancer at different thresholds using nine variables related to patient and imaging characteristics. Analysis was performed per patient based on the largest nodule. Lung-RADS and VRC using the 5% threshold were compared to assess diagnostic performance in determining the risk of developing lung cancer in a patient with a nodule found at screening CT. The McNemar test was used to compare differences in performance between Lung-RADS and VRC.

RESULTS

Lung-RADS resulted in nine false-positive and 16 false-negative findings, whereas VRC with a 5% threshold resulted in 29 false-positive and 10 false-negative findings. Overall sensitivity and specificity for Lung-RADS was 58.0% and 98.0%, and for VRC with a 5% threshold was 73.7% and 93.5%, respectively (P = .313, P < .001, respectively).

CONCLUSION

The VRC performs well in an urban, diverse lung cancer screening program. Further studies may be directed at determining whether its use in conjunction with Lung-RADS leads to improved lung cancer detection.Keywords: CT, Lung, Thorax© RSNA, 2020.