Research on lung cancer leads to changes in national guidelines for screening eligibility.
Dr. Julie Palmer
1/16/2026
Early detection of lung cancer through low-dose computed tomography (LDCT) screening is one of the most promising strategies to reduce lung cancer mortality in high-risk individuals. LDCT screening is recommended by the United States Preventive Services Task Force (USPSTF), the American Cancer Society (ACS), and the National Comprehensive Cancer Network (NCCN) for individuals who meet certain age and smoking history criteria. The USPSTF guidelines were updated in 2021 to expand the eligible age group from 55-80 to 50-80, and to reduce the required number of pack-years of smoking from 30 to 20.
Dr.Julie Palmer, the Karin Grunebaum Professor in Cancer Research at the Boston University Chobanian and Avedisian School of Medicine and Dr. Chi-Fu Jeffrey Yang, a thoracic surgeon and lung cancer researcher from the Massachusetts General Hospital and Harvard Medical School have been working together to assess how well the revised guidelines work in the Black population.
Our most recent report on this topic, published in the Journal of Clinical Oncology in 2024, was based on data from both the Black Women's Health Study and the Southern Community Cohort Study - a study from Vanderbilt University. We showed that using a 20-pack-year smoking history cutoff as a selection criterion for lung cancer screening excluded many study participants who had been diagnosed with lung cancer, and led to a marked racial disparity in screening eligibility between Black versus white individuals, with a higher proportion of white patients identified as high risk.
Applying a 20-year smoking duration cutoff (instead of pack-years) increased the proportion of lung cancer patients who would qualify for screening and, importantly, eliminated the racial disparity in screening eligibility.
In the paper, we further noted that a guideline of 20 years duration of smoking would be easier for clinical use. Following publication of our paper, the NCCN revised their guidelines for lung cancer screening in October 2024. Under the new guidelines, individuals who are age 50 or older and have smoked for at least 20 years or have 20 pack-years of smoking are deemed eligible for screening by low-dose CT scan.
Citations: Potter AL, Xu NN, Senthil P, Srinivasan D, Lee H, Gazelle GS, Chelala L, Zheng W, Fintelmann FJ, Sequist LV, Donington J, Palmer JR & Yang CJ. Pack-Year Smoking History: An Inadequate and Biased Measure to Determine Lung Cancer Screening Eligibility. J Clin Oncol. 2024 Jun 10;42(17):2026-2037. doi: 10.1200/JCO.23.01780. Epub 2024 Mar 27. PMID: 38537159