Breath Test Helps Detect Early Lung Cancer: Study

A simple test of exhaled breath can help detect early onset lung cancer, according to a new study.

Researchers from the University of Louisville have discovered a test that helps diagnose lung cancer in the early stages. The presence of certain carbonyl volatile organic compounds (VOC) in exhaled breath helps detect cancer.

The study authors identified four markers , or carbonyl VOCs in the breaths of 10 lung cancer patients along with 88 controls. Further study of 151 subjects was done of which 109 were diagnosed with lung cancer and 42 with benign nodules. Their exhaled breaths were collected using a 1-L Tedlar bag and were analyzed for the specific VOCs that could be used along with computer tomography (CT) for early detection of lung cancer. It was found that when levels of three or more VOCs went up, the sensitivity and specificity for cancer were between 60 and  95 percent, respectively.

 Michael Bousamra, M.D and associate professor at Department of surgery, University of Louisville said in a press statement,  "When three or four carbonyl markers were elevated, the probability of cancer was very high; when no carbonyl markers - or even one - was elevated, associated pulmonary disease was likely benign. I think that clinical decision making could be assisted in these instances."

He also added that Carbonyl VOC testing might become a regular clinical practice within two years. Previous studies considered exhaled breath  as a promising non invasive tool for the early detection of lung cancer but failed to achieve clinical significance due to lack of specificity and challenges associated in complex mixtures of VOCs.

According to the American Lung Association, lung cancer caused nearly 28 percent (approximately 160,340 Americans) of all cancer deaths in the U.S. during 2012. Kentucky has the highest smoking rates and lung-cancer incidences in the country.

Dr Tom Varghese Jr from the University of Washington, says the new testing represents a window into the future of lung cancer screening. He adds, "Such screening, if applied using strict criteria, would avert 12,000 lung cancer deaths today."