Lung cancer is often difficult to diagnose early, especially when small lung nodules appear on imaging scans. Researchers from Veracyte, Inc have developed the Percepta Nasal Swab (PNS) test, a noninvasive method that uses RNA sequencing (RNA-Seq) to assess lung cancer risk in individuals with a history of smoking.

Cigarette smoke affects gene expression throughout the respiratory tract, including the nasal epithelium. The PNS test takes advantage of this biological response by analyzing gene expression changes in nasal cells using whole transcriptome sequencing. Based on the results, the test classifies patients into high, intermediate, or low-risk groups, helping doctors make more informed decisions about follow-up care.

To ensure the reliability of this test, the researchers evaluated its accuracy, reproducibility, and sensitivity under different laboratory conditions. They tested how well results remained consistent across different laboratories and under varying RNA sample qualities. The study found that the PNS test maintained strong performance, with minimal variability in results and resistance to common sample issues, such as contamination with genomic DNA or blood RNA.

Analytical sensitivity of PNS to RNA input

The y-axis is a relative scale, with 0 representing the mean score of each sample across all input levels. Scores of the downstream model is shown here in the boxplot with the horizontal line in each boxplot indicating the median value. Each RNA input amount was run in triplicate for each sample. The region between the two dashed blue lines (0.4) represents 5.87% of the 98 percentiles of the PNS score range

These findings confirm that the PNS test is a reliable tool for assessing lung cancer risk, offering a noninvasive way to guide clinical decisions and reduce unnecessary procedures for patients with indeterminate lung nodules.