A simple, inexpensive breath test may be key to determining the return of lung cancer after surgery, according to a new study.
A team of researchers from the University of Louisville in Kentucky has found that three chemical markers identified as carbonyl compounds – among the gases released as people exhale – were diminished in lung cancer patients after their tumor removal surgery.
Exhaled breath comes with volatile organic compounds (VOCs) by the thousands, varying in pattern and composition depending on one’s well-being. Identifying the “signature” of lung cancer is then deemed promising in easily diagnosing the disease and monitoring for recurrence.
The team investigated breath samples from before and after the surgery of 31 persons with lung cancer, comparing carbonyl compound levels with those from 187 healthy counterparts. Overall carbonyl VOCs in the cancer patients were significantly reduced post-surgery, with three out of four normalized after the procedure and matching those in the healthy group.
“[This] provides strong evidence that they are directly produced by the tumor environment. This study confirms that the technology is accurate,” explained lead author Dr. Erin Schumer.
Here’s how the breath test is done. A user blows a single breath into a specially constructed balloon, which is linked to a pump pulling the breath over a tiny microchip that traps the chemicals. The microchip goes to the laboratory for analysis in a couple of hours.
The technology is deemed practical and convenient, such that breath collection can be done in a doctor’s office. The pump can be reused, while the tools and lab test combined cost only about $20 for an easy, non-invasive lung cancer diagnosis.
The breath test can detect lung cancer whether as a primary screening technique or as follow-up after disease treatment, said co-author Dr. Victor van Berkel, broaching the team’s plan to seek FDA approval.
Lung cancer remains the most deadly form of cancer, estimated to afflict 224,000 in the United States this year alone. Over 158,000 of its patients will die, translating to 433 deaths a day.
At present, patients are tested after surgery via chest CT scans, which can be costly and source of radiation exposure.
Dr. Inga Lennes of the Massachusetts General Hospital in Boston, who was not connected with the research, warned in a Live Science report that up to 30 percent of patients getting those existing lung screening methods are discovered to have lung nodules – yet a tiny percentage of those nodules actually turn out cancerous.
"Anything that moves us forward to finding lung cancer earlier is a step forward for the whole field," said Lennes, welcoming the results from the new study.
The findings were detailed in the journal The Annals of Thoracic Surgery.
Photo: Lorraine Santana | Flickr