Breath Test Helps Spot Lung Cancer

The research, though preliminary, was accurate about 75% of the time.

By Amanda Gardner
HealthDay Reporter
Tuesday, February 27, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

MONDAY, Feb. 26 (HealthDay News) -- The future of lung cancer detection may involve a simple, inexpensive breath test that can pick up the chemical "signature" of patients with the disease, a new study suggests.

"Think of it as a proof of principle study," said Dr. Peter Mazzone, lead author of the study and director of the lung cancer program at the Cleveland Clinic. "But there's still quite a bit more work to be done, and I would put it in the five-to-10-year range."

People have a variety of different chemicals, called volatile organic compounds (VOCs), present in their breath. Different diseases are thought to alter the production or processing of these chemicals in a way that can be detected.

The earliest studies looking at this phenomenon compared the chemicals and their concentrations in lung cancer patients and healthy patients.

"That equipment was expensive and difficult to use and interpret," Mazzone said. "It would be nice, in order to bring it right to the patient, if you had simple-to-use devices that were equally accurate."

The sensor that's the focus of the new study, a colorimetric sensor array, is related to other sensors used for sniffing out bombs at airports or checking to see if vegetables are going bad in a grocery store.

Rather than determine the exact chemicals and their concentrations, this sensor changes color depending on the pattern of chemicals. The device is about the size of a nickel and has 36 dots, each made up of a different chemical.

"The color of that dot changes based on what chemicals are absorbed into it," Mazzone explained. "So, the pattern of chemicals in the breath is represented by patterns of color changes on the sensor."

Lung cancer remains the No. 1 cancer killer of both men and women in the United States. A main reason for the high death toll: About 70 percent of lung cancers are diagnosed in the late stages.

"The most useful part of any new test would be if we're able to accurately and inexpensively detect very early stage lung cancer when it could be cured," Mazzone said. "That would be the holy grail."