Blood-Based Immune Signal Could Reveal Lung Cancer Risk Before Tumors Develop

In the U.K., about 32,800 people die from lung cancer each year, and only 11.1% of those diagnosed are predicted to survive 10 years or more. Earlier identification of high-risk individuals remains a major diagnostic challenge. To support earlier risk detection, new findings demonstrate a blood-based immune signal that may indicate lung cancer risk years before a tumor develops.

University College London (UCL) researchers identified a preinvasive regulatory T cell axis linked to lung cancer interception. The work used prototype blood tests to follow what the researchers described as an immune “fog.” This signal involved regulatory T cells, or Tregs, which are specialized immune cells that can hold back other immune cells and pause their activity. The buildup of Tregs occurred months or years before cancer developed.

The team studied blood and tissue samples from people enrolled in long-running lung cancer surveillance and screening studies. Similar processes were also analyzed in mice to examine how lung cancer precursors, described as precancers or lesions, can develop into full tumors. The study found that monitoring Treg levels could help identify people at increasing risk of lung cancer or patients with an early form of the disease.

The researchers also examined whether targeted cancer drugs could reverse and disperse the Treg “fog.” A drug targeting specific immune processes reversed the immune-suppressing effect of Tregs. In laboratory experiments, this approach halved the proportion of animals that developed lung tumors and prevented the formation of all large tumors. The findings were published in Nature on October 7, 2026.

“This study provides valuable new insight into the early stages of lung cancer development. By identifying mechanisms that could both signal increased risk and offer opportunities for intervention, this research highlights the potential of discovery science to underpin new approaches to cancer prevention and early detection,” said Dr. Charlotte Durkin, associate director of molecular and cellular medicine at MRC.

Related Links
University College London