New Blood Test Shows Promise in Predicting Lung Cancer Before It Starts

Scientists are exploring a groundbreaking approach that could transform lung cancer prevention - a blood test capable of identifying people at high risk years before cancer develops. Cancer is among the deadliest diseases across the world, causing approximately 1.8 million deaths each year. While smoking remains the leading risk factor, air pollution and occupational exposures also contribute significantly to the disease burden. A multinational team of researchers led by Charles Swanton at the Francis Crick Institute recently reported a major discovery in the journal Cell. The scientists identified a “14-protein signature” in blood plasma that may predict the likelihood of developing lung cancer years before diagnosis, opening the door to earlier

intervention and potentially life-saving preventive treatments.Also read: 30 Years of Research Suggests THIS Beverage May Be the Ultimate Health Drink

How can a blood test predict future lung cancer?

The new research focuses on blood plasma, the liquid component of blood that carries thousands of proteins released by organs and tissues throughout the body. Together, these proteins form the plasma proteome, which can provide valuable insights into a person's health. Researchers describe plasma analysis as a type of “liquid biopsy” because it offers a snapshot of biological changes occurring inside the body. By comparing protein profiles from healthy individuals and those who later developed lung cancer, scientists hoped to identify early warning signs of disease. To achieve this, the research team used data from the UK Biobank, a long-running health project tracking around 500,000 volunteers. The database contains anonymized health records and biological samples that help scientists study disease development over time. Using plasma samples from nearly 48,000 participants, researchers trained a machine-learning model to analyze protein patterns alongside factors such as age, sex, smoking status, and lung cancer diagnosis history. The model identified 14 proteins strongly associated with future lung cancer risk.

Remarkably accurate predictions

The team then tested the model on data from approximately 12,000 participants who were not included in the training phase. Among this group were 75 individuals who later developed lung cancer, with a median diagnosis time of 5.1 years after blood sampling. Impressively, the model correctly identified more than 75 per cent of future lung cancer cases, demonstrating high sensitivity. Researchers also validated the 14-protein signature across eight additional datasets, including lifelong non-smokers, suggesting that the biomarker may be useful beyond traditional high-risk populations.

The link between inflammation and cancer

The study revealed that the protein signature became more pronounced when inflammatory pathways associated with smoking and air pollution were activated. Previous research by the same team suggested that air pollution can trigger inflammation that awakens dormant, mutated lung cells, eventually allowing them to develop into cancer. The new findings support a theory that smoking may cause genetic mutations, while inflammation acts as the catalyst that drives cancer formation. The signature was also stronger among people who later developed chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis, both conditions linked to chronic lung inflammation.

Could existing drugs prevent lung cancer?

The researchers also identified a potential preventive treatment. They examined data from the CANTOS trial, which studied a drug called Canakinumab for reducing inflammation after heart attacks. A retrospective analysis found that participants displaying the 14-protein signature experienced a 50% reduction in lung cancer risk when treated with canakinumab. While the findings are encouraging, experts caution that canakinumab has significant drawbacks, including serious side effects and high costs. Further studies are needed to determine whether safer and more affordable alternatives can achieve similar results.

What happens next?

Although the discovery is exciting, researchers stress that the 14-protein signature still requires validation in more diverse populations worldwide. Scientists must also develop a practical diagnostic test capable of measuring all 14 proteins accurately and cost-effectively. If future studies confirm these findings, healthcare providers may one day use a simple blood test to identify people at high risk for lung cancer years before symptoms appear. Combined with targeted preventive treatments, this approach could revolutionize cancer prevention and save countless lives. For now, the research represents a significant step toward earlier detection, personalized risk assessment, and a future where lung cancer can be stopped before it starts.