Lung cancer screening scans can sometimes reveal signs of other, previously undiagnosed cancers, according to research published on Mar. 31 by Brown University School of Public Health.
The findings are important as they suggest that routine lung cancer screenings using computerized tomography (CT) scans could help doctors identify cancers outside the lungs at an earlier stage. This could lead to improved outcomes for patients who might otherwise remain undiagnosed until their disease has progressed.
Researchers analyzed data from more than 26,000 participants in the National Lung Screening Trial, a large federal study that established CT scans as a standard method for screening high-risk individuals such as longtime smokers. The study found that certain abnormalities detected during these scans were linked to a higher likelihood of being diagnosed with extrapulmonary cancers—cancers located outside the lungs—within one year.
"For both patients and doctors, the results offer clearer guidance on what it means when a scan reveals something unexpected, and which types of abnormalities are more likely to be a sign of an extrapulmonary cancer," the authors said in their report published in JAMA Network Open. They also noted that balancing early detection with avoiding unnecessary tests is an ongoing challenge in modern medicine.
According to the study's results, about 3% of all screening rounds and nearly 7% of participants had findings potentially related to cancer across more than 75,000 CT scans over three rounds. Those with such abnormalities faced significantly higher risks for developing urinary system cancers like kidney and bladder cancer as well as lymphoma and leukemia within a year.
Lead researcher Gareen said she plans future studies to determine if these findings hold true among patients screened in community settings rather than clinical trials. Other contributors included researchers from several institutions such as Duke Health and Massachusetts General Hospital. The National Cancer Institute funded this research.
