Researchers have found that adopting a Lung Nodule Program may increase early lung cancer detection in patients who are not eligible for lung cancer screening under existing age-eligibility criteria, according to a recent study published by Liao et al in the Journal of Thoracic Oncology.
Background
The U.S. Preventive Services Task Force currently recommends screening for lung cancer annually with low-dose computed tomography (CT) in adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or have quit smoking within the past 15 years. Low-dose CT screening for lung cancer has been shown to reduce the mortality rate by up to 20%; however, even after lowering the screening eligibility age from 55 to 50 years, most U.S. patients diagnosed with lung cancer may still be ineligible for lung cancer screening.
Lung Nodule Programs—which typically use the Fleischner Society’s lung nodule management guidelines—may expand access to early lung cancer detection for a more diverse population. The programs are established to follow-up on lung nodules frequently identified during routine imaging for reasons other than suspected lung cancer or lung cancer screening. The risk of lung cancer among patients deemed too young or too old for screening, but who receive an incidentally detected lung lesion, has not previously been studied rigorously.
Study Methods and Results
In the new prospective observational study, the researchers compared the 2-year cumulative lung cancer diagnosis risks, lesion characteristics, lung cancer characteristics, treatments, and outcomes of patients enrolled in a Lung Nodule Program who were screening age–ineligible to those who underwent low-dose CT screening between 2015 and 2022. The patients who participated in the Lung Nodule Program were aged 35 to 50 years and over 80 years, and the patients who underwent the low-dose CT screening were aged 50 to 80 years.
The researchers discovered that 3.43% (n = 329) of the patients in the low-dose CT screening cohort vs 1.07% (n = 39) and 6.87% (n = 172) of the respective younger and older patients in the Lung Nodule Program were diagnosed with lung cancer. Further, the 2-year incidence rates of lung cancer were 3.0% (95% confidence interval [CI] = 2.6%–3.4%) among those who received low-dose CT screening, 0.79% (95% CI = 0.54%–1.1%) among those enrolled in the Lung Nodule Program who were younger than the recommended screening ages, and 6.5% (95% CI = 5.5%–7.6%) among those enrolled in the program who were older than the recommended screening ages.
Despite the age differences, the risk of receiving a lung cancer diagnosis was found to be similar between younger patients in the Lung Nodule Program cohort and Lung CT Screening Reporting and Data System 1 (adjusted hazard ratio [HR] = 0.88, CI = 0.50–1.56) and 2 (adjusted HR = 1.0, CI = 0.58–1.72). In contrast, the risk of diagnosis among older patients in the Lung Nodule Program cohort exceeded that of Lung CT Screening Reporting and Data System 3 (adjusted HR = 2.34, CI = 1.50–3.65) but was less than 4 (adjusted HR = 0.28, CI = 0.22–0.35).
Additionally, the researchers found significant differences in the stage at time of cancer diagnosis—where 62.92% of the cases diagnosed in the low-dose CT screening cohort were stages I or II compared with 33.33% in the younger Lung Nodule Program cohort (P = .0003) and 48.26% in the older Lung Nodule Program cohort (P = .0004). They also noted that 16.72%, 41.03%, and 29.65% of the cases in the respective low-dose CT screening, younger Lung Nodule Program, and older Lung Nodule Program cohorts were diagnosed at stage IV and the 5-year overall survival rates were 57% (CI = 48–67), 55% (CI = 39–79), and 24% (CI = 15–40), respectively—with statistically significant differences (Log-rank P < .0001) persisting even after excluding patients with a prior history of cancer.
Conclusions
"Our findings indicate that our Lung Nodule Program modestly benefitted individuals deemed too young or too old for traditional screening,” emphasized senior study author Raymond U. Osarogiagbon, MBBS, FACP, Chief Scientist at Baptist Memorial Health Care and Director of the Multidisciplinary Thoracic Oncology Program and the Thoracic Oncology Research Group at the Baptist Cancer Center. “The observed differences in clinical characteristics and outcomes strongly suggest variations in the biological characteristics of lung cancer in these distinct patient cohorts,” he concluded.
Disclosure: For full disclosures of the study authors, visit jto.org.
