Predicting Lung Cancer: Risk-Based LDCT Screening vs Age and Pack-Years

Screening via risk-based low-dose computed tomography (LDCT) is a better predictor of lung cancer risk than age and pack years. Early involvement of a lung nodule specialist leads to the detection of a high percentage of early-stage cancers and few benign resections. These results from a recent study conducted at Mayo Clinic were presented at the American Thoracic Society (ATS) 2022 Annual Meeting, held in San Francisco, CA, May 13 to 18.

The researchers evaluated screening candidates for high-risk status, as evidenced by US Preventive Services Task Force (USPSTF) criteria or a Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO)_m2012 Screening Trial risk predictor score ≥1.34%; candidates deemed high-risk status were followed over the next 6 years. No assessment other than the next annual or follow-up LDCT was recommended for individuals with Lung CT Screening Reporting & Data System (Lung-RADS) scores 1 to 3. Lung-RADS 4 scores prompted review by a pulmonologist, followed by a possible clinic visit and additional testing.

A total of 2625 participants were enrolled and had at least 1 LDCT. Of those screened by LDCT, 2195 (84%) were eligible for screening using both USPSTF criteria and PLCO_m2012 scores, 250 (9%) qualified by PLCO _m2012 scores alone, and 178 (7%) qualified by USPSTF criteria alone.

Lung cancer was detected in 123 participants. The following types were identified: 112 screen-detected non-small cell lung cancers (NSCLCs) in 102 patients (prevalence, 83 [3.2%]; incidence, 29 [1.1%]), 10 screen-detected small cell lung cancers(SCLCs), and 6 between-screening interval cancers. An additional 5 cancers were identified more than 2 years after screening cessation.

The mean PLCO _m2012 risk calculation was 8.21% (range, 0.9-34.6) for participants with cancer, vs 5.20% (range, 0.1-52.1) for those without. In all, 82 (73%) stage I or II screen-detected NSCLCs were observed, and 4 (5.8%) participants had benign surgical resections out of a total of 69 surgeries. Just 2 patients with cancer qualified for screening solely by USPSTF criteria, whereas 8 with cancer qualified by PLCO _m2012 scores alone.

“LDCT screening for lung cancer using an individual risk calculation is feasible in community and academic setting and is a better predictor for lung cancer development than age and pack-years alone,” the authors concluded.

Reference

Midthun DE, Rode MM, Sykes A-M, et al. Risk-Based Lung Cancer Screening in the Mayo Clinic Lung Screening Program. Presented at: the American Thoracic Society (ATS) 2022 International Conference; May 13-18, 2022; San Francisco, CA. Abstract 219.

This article originally appeared on Pulmonology Advisor