The following is a summary of “Outcomes From More Than 1 Million People Screened for Lung Cancer With Low-Dose CT Imaging,” published in the July 2023 issue of the Chest by Silvestri et al.

In 2013, low-dose CT (LDCT) imaging was recommended for lung cancer screening (LCS), making approximately 8 million Americans eligible. The population-level demographic characteristics and outcomes of individuals screened in the United States have yet to be reported. How do the outcomes of those screened and submitted to the Lung Cancer Screening Registry of the American College of Radiology compare to those of trial participants? Between 2015 and 2019, the participants in this cohort investigation underwent baseline LDCT imaging for LCS. Predictors of annual screening compliance were calculated. 

Researchers compared National Lung Cancer Screening Trial data with LDCT scan interpretations by Lung Imaging Reporting and Data System (Lung-RADS) score, cancer detection rates (CDRs), and stage at diagnosis. Predictors of poor adherence included current smoking status and Hispanic or Black race. The adherence rate was 22.3%. About 83% of patients screened at baseline had negative findings, while 17% had positive results. Overall, the CDR was 0.56%. In the positive Lung-RADS categories, the percentage of individuals with cancer detected at baseline was higher: 0.4% for Lung-RADS category 3, 2.6% for Lung-RADS category 4A, 11.1% for Lung-RADS category 4B, and 19.9% for Lung-RADS category 4X. 

Similar to what was observed in the National Lung Cancer Screening Trial, 53.5% of patients have been diagnosed with stage I and 14.3% were diagnosed with stage IV cancer. Underreporting may have occurred in the registry. This study disclosed the benefits and challenges of lung cancer CT scan screening. The correlation between CT findings and lung cancer detection using the Lung-RADS system was accurate. Significant progression to the early stages of lung carcinoma was observed. Poor adherence to LCS likely contributes to the lower-than-anticipated cancer detection rate, all of which will impact the outcomes of lung cancer screening patients.

Source: sciencedirect.com/science/article/abs/pii/S0012369223001757