Data from the American Lung Association ranks lung cancer as the leading cause of cancer-related mortality in both men and women – having a mortality rate higher than the next three most prevalent cancers put together: colon, breast and prostate cancer. It has even overtaken breast cancer as the major cause of cancer-related death in women. In order for lung cancer to be diagnosed, patients have to undergo a series of procedures, but interestingly, a group of scientists made a recent discovery that certain compounds can be detected in an individual’s exhaled breath and be analysed for the presence of the disease — an approach that could potentially be adapted for a wide range of other pulmonary diseases, such as COPD.
This potentially groundbreaking method of detecting lung cancer in its early stages comes from a group of researchers at the University of Louisville. Dr. Michael Bousamra and colleagues presented their investigation and findings during the 50th Annual Meeting of the Society of Thoracic Surgeons held in Orlando, Florida earlier this week. Bousamra and his fellow researchers decided to explore the possibility of this diagnostic method after evaluating patients with “suspicious” lesions in the lungs.
The team employed a silicone microprocessor and mass spectrometer to conduct tests on the exhaled breaths of individuals suspected to have the disease, in order to identify the presence of particular volatile organic compounds (VOCs) called carbonyls. These compounds consist of aldehydes and ketones – compounds with carbon and oxygen molecules sharing double bonds – and are only present in minute amounts from the body.
The team took the data obtained from these tests and related it to findings from pathologic and clinical tests. They discovered that 95% of the tested individuals known to have a lung mass had 3-4 carbonyl compounds strongly associated with the presence of cancer.
While Bousamra explained that their findings are still preliminary, he did not neglect to point out that the absence of high levels of VOCs were more indicative of a benign mass in 80% of patients known to have a respiratory mass.
Bousamra and his team also noted that upon removal of these malignancies in select patients, the previously detected high levels of VOCs decreased to normal levels.
“Instead of sending patients for invasive biopsy procedures when a suspicious lung mass is identified, our study suggests that exhaled breath could identify which patients may be directed for an immediate intra-operative biopsy and resection … The novelty of this approach includes the simplicity of sample collection and ease for the patients.” – Dr. Michael Bousamra, University of Louisville
As for efforts by agencies to reduce the public’s risk of lung cancer, the US Preventive Services Task Force has just endorsed revised guidelines for lung cancer screening in older smokers. These guidelines involve a yearly low-dose computed tomography (CT) pulmonary screening. The same possible efficacy for lung cancer screening could potentially be applied to COPD as well. According to a clinical trial study abstract on PubMed, a group of researchers have already completed a compelling study on exhaled breath condensate biomarkers in COPD, since “biomarkers in chronic obstructive pulmonary disease may be useful in aiding diagnosis, defining specific phenotypes of disease, monitoring exacerbations and evaluating the effects of drugs. Exhaled breath condensate is a noninvasive means of sampling the airways, allowing biomarkers of airway inflammation and oxidative stress to be measured.”