The International Agency for Research on Cancer (IARC) has published a comprehensive international evaluation on lung cancer screening in The New England Journal of Medicine.
Screening has emerged as a complementary approach to tobacco control and other methods for preventing lung cancer to reduce the quantity of deaths from lung cancer. Lung cancer screening especially enables earlier disease detection, allowing more cancers to be identified while they are at a more manageable, treatable stage.
“With lung cancer continuing to be the leading cause of cancer death worldwide, we urgently need to strengthen both prevention and early detection,” said co-author Béatrice Lauby-Secretan, PhD, MSc, Head of the IARC Handbooks of Cancer Prevention Program.
As part of the IARC's Handbooks of Cancer Prevention program, the IARC convened a working group of 23 clinicians and scientists from across 17 countries to collectively assess the benefits, harms, and effectiveness of lung cancer screening.
The published report highlights the major international trials, real-world implementation studies, and other clinical evidence reviewed by the working group, as well as their conclusions on lung cancer screening. Among the evaluated studies included were experimental and observational epidemiologic studies that explored the benefits and harms of lung cancer screening with either low-dose computed tomography (CT) or chest radiography, with or without cytologic sputum evaluation. The group focused on outcomes of lung cancer mortality and the incidence of stage III–IV disease. Potential harms considered included false positive rates, overdiagnosis, radiation-induced cancers, and psychological effects.
“Lung cancer screening has the greatest potential when it reaches the people most likely to benefit and is embedded within broader cancer prevention efforts,” Dr. Lauby-Secretan said. “Our rigorous, transparent, and independent expert evaluation brings together the available evidence to provide countries with a robust, evidence-based foundation for decisions about how lung cancer screening should be targeted, implemented, and integrated with tobacco control and cancer prevention.”
Consideration was also given to cost-effectiveness, emerging technology including artificial intelligence for assisted image analysis, risk prediction models, nodule malignancy prediction, molecular biomarkers, smoking cessation interventions, and other assessments for the overall effectiveness and reach of lung cancer screening programs.
The working group ultimately decided that screening individuals who are at high risk for lung cancer with low-dose CT screening, based on age and smoking history, reduces lung cancer–specific mortality as well as the incidence of more advanced-stage disease. They were not able to classify if chest radiography, with or without sputum cytology, was able to reduce lung cancer incidence or mortality.
“These findings provide an important evidence base for countries considering how lung cancer screening may fit within their own health systems. We reviewed not only mortality reduction, but also implementation, participation, smoking cessation, artificial intelligence, and emerging technologies, providing a much clearer understanding of who benefits most, how programs can be delivered, and how screening can be combined with smoking cessation and other interventions to maximize public health impact,” Dr. Lauby-Secretan said.
The study authors noted, however, that the findings should be considered within the context of each country's capacity and resources, and that screening should complement but not replace effects toward tobacco control and smoking cessation to prevent lung cancer.
A review of the evidence reviewed on lung cancer screening was also presented at the World Cancer Congress in Hong Kong, China.
DISCLOSURES: For full disclosures of the study authors, visit nejm.org.
