Breathe to Detect Lung Cancer

Raphael Nnadi

January 29, 2026
3:03 pm

Swedish researchers have developed a breakthrough method to detect lung cancer through a single breath test, potentially identifying tumors smaller than a millimeter before they appear on traditional scans. The technology, which received $1.9 million in funding from Sweden’s cancer foundation, could revolutionize screening for one of Denmark’s deadliest cancers.

A Revolutionary Approach to Early Detection

Lung cancer remains one of the most lethal forms of cancer in Denmark. Around 5,000 Danes receive the diagnosis each year, and the disease is often discovered at advanced stages when treatment options are limited. However, researchers at Lund University in Sweden have made significant progress on a method that could change this reality dramatically.

The new technique involves collecting and analyzing a patient’s exhaled breath. According to the research team, this simple test can detect lung cancer much earlier than current imaging methods allow. Ole Hilberg, professor and chief physician at the Danish Research Center for Lung Cancer, acknowledges the potential significance of this development.

The method would make it possible to screen high-risk patients without requiring CT scans, which represent both a logistical and financial burden on healthcare systems. While several countries have been working on breath-based diagnostic tools, the Swedish team appears closer to practical implementation than previous efforts.

How the Breath Test Works

The diagnostic approach relies on collecting microparticles present in exhaled air. These particles contain proteins and RNA from lung tissue, and researchers can identify patterns indicating cancer when they analyze these components.

In their unpublished study, the Swedish team collected breath samples from patients scheduled for lung cancer surgery. They took samples both before and after tumor removal, then compared these with samples from healthy individuals. This approach allowed researchers to pinpoint which markers correlate with cancer and which disappear once the tumor is removed.

Detecting Multiple Cancer Types

Surprisingly, the breath analysis doesn’t just indicate whether cancer is present. The test can distinguish between the two most common types of lung cancer: small cell and non-small cell. This differentiation is crucial because these cancer types require different treatment approaches.

The preliminary results suggest that even very small tumors leave measurable traces in exhaled breath. According to Sandra Lindstedt, research leader at Lund University, the method provides access to information that can be difficult to detect through traditional imaging.

Why Early Detection Matters

Currently, detecting lung cancer requires relatively large changes in the lungs before abnormalities become visible on X-rays or CT scans. The smallest tumors can be particularly challenging to identify. Traditional imaging methods often miss early-stage cancers that might be easier to treat successfully.

With the new breath-based method, researchers believe they can detect tumors smaller than a millimeter. This represents a substantial improvement over current diagnostic capabilities. For patients, earlier detection often translates directly to better survival rates and more treatment options.

The Cancer Burden in Denmark

Approximately 45,000 Danes are diagnosed with cancer each year, making it the leading cause of death in the country. Lung cancer specifically ranks among the most deadly forms, with primary causes linked to smoking. Despite recent advances in cancer research improving survival rates, lung cancer continues to cause more cancer-related deaths than any other type in Denmark.

Two main types of lung cancer exist: small cell and non-small cell, each requiring different treatment protocols. While survival rates have been increasing in recent years thanks to ongoing research, the disease remains extremely serious.

Significant Financial Investment

The Swedish cancer foundation demonstrated strong confidence in this research by awarding the project 27 million Swedish kronor, equivalent to approximately 19 million Danish kroner. This substantial investment will enable researchers to further develop the technology.

As Ole Hilberg points out, when a project receives this level of funding, it signals that reviewers believe in both the concept and the underlying data. However, because the study remains unpublished, determining the exact margins of error and reliability proves difficult at this stage.

The Screening Process

If approved and standardized, the breath test could be deployed at both hospitals and smaller clinics throughout Denmark and Sweden. The process would work through several steps. First, exhaled air gets collected from individuals at increased risk for lung cancer, such as smokers or previous cancer patients. The air contains microparticles with proteins and RNA carrying traces from lung tissue.

After collecting these particles into a sample, researchers quantify levels of thousands of biomarkers. Machine learning algorithms then calculate the probability that a patient has lung cancer based on these measurements. This approach offers a fast and gentle screening method compared to radiation-based imaging.

Impact on Survival Rates

A 2020 European study demonstrated that lung cancer screening increases survival by 25 percent. If the breath-based method receives approval, this percentage could potentially climb even higher. The ability to detect cancer at earlier stages naturally improves treatment outcomes and gives patients more options.

Ole Hilberg emphasizes that if the method proves effective, its adoption in Denmark is practically guaranteed. At the same time, making the technology widely accessible remains crucial. Ideally, general practitioners or multiple facilities across the country should be able to offer the test, rather than limiting it to specialized centers.

Timeline and Next Steps

While the current findings appear promising, researchers have considerable work ahead. The study needs publication in a peer-reviewed journal, allowing the broader medical community to examine the methodology and results. Following that, larger clinical trials will be necessary to verify the test’s accuracy across diverse populations.

Sandra Lindstedt expressed hope that the method could eventually serve as a screening tool not just in hospitals but also at health centers, making it accessible to a broader population. This widespread availability would be essential for the technology to achieve its full potential in reducing lung cancer deaths.

For now, the research team will focus on refining the technology and conducting additional studies with the funding they’ve received. Meanwhile, Danish medical professionals like Ole Hilberg are watching developments closely, eager to see whether this breakthrough will translate into practical benefits for patients.

The technology represents more than a decade of work on breath-based diagnostics. According to Hilberg, researchers are now closer than ever to making this approach a clinical reality. If successful, the simple act of breathing into a collection device could save thousands of lives annually by catching lung cancer at its most treatable stages.