The test needs refinement, but the theory behind the test works, say the doctors who developed it.
The Cleveland Clinic's Peter Mazzone, MD, MPH, and colleagues describe the test in the "Online First" edition of the journal Thorax.
The test measures chemicals called volatile organic compounds (VOCs) in the breath. Specifically, the test screens for a pattern of VOCs associated with lung cancer.
For the test, patients simply breathe into a device for several minutes.
The device funnels breath across a quarter-sized panel studded with 36 little dots. The dots change color based on the VOCs in the patient's breath.
Mazzone and colleagues tried the test on 143 people, including 49 with lung cancer, 73 with other lung diseases, and 21 without lung cancer or any lung disease. Each patient breathed into the device for 12 minutes.
The key questions: How accurate was the test in spotting any lung disease, and how accurate was it at specifically spotting lung cancer? The result: The test was promising but not perfect.
The test correctly identified nearly three out of four people with any lung disease and specifically spotted lung cancer almost as frequently.
The test has "moderate accuracy" and needs more work, but it could "ultimately ... lead to an inexpensive, noninvasive screening or diagnostic test for lung cancer," write the researchers.