Diagnosing mesothelioma may one day be as simple as taking a breath test.
A team of researchers in the Netherlands have been testing the effectiveness of an electronic nose in detecting mesothelioma, a fast-growing cancer caused by exposure to asbestos. Mesothelioma is notoriously difficult to diagnose because it often mimics other lung-related diseases. In addition, some of the most effective methods for diagnosing mesothelioma carry a high risk of complications, especially in the elderly – the group most likely to get the disease because of its long latency.
Doctors in the Department of Respiratory Medicine at the University of Amsterdam Medical Center conducted an experiment to determine whether an electronic nose called the Cyranose 320 could tell the difference between healthy people, people with mesothelioma, and people who had long-term exposure to asbestos but did not have mesothelioma. The Cyranose 320 is a handheld direct reading electronic nose with a 32-sensor chip. It can be trained to recognize a wide range of odorant molecules and construct a ‘smellprint’ of chemical compounds that are indicative of a particular disease. More than 3,000 volatile organic compounds can be present in exhaled breath.
For their study, the Dutch researchers recruited 13 patients with confirmed mesothelioma and 13 patients with certified, long-term professional asbestos exposure. Thirteen healthy people without asbestos exposure served as the control group. Exhaled breath was collected from each group and sampled by the electronic nose. The resulting “breathprints” were analyzed, the individual volatile organic compounds found in each subject’s breath were mapped, and the results were cross-checked for accuracy.
The results were encouraging for those searching for an easier, more accurate method of diagnosing mesothelioma. The electronic nose easily distinguished the mesothelioma patients from those who had been exposed to asbestos with 92.3% sensitivity and 85.7% specificity. Mesothelioma patients were also distinguished from the healthy controls. Repeated measurements yielded the same results.
In drawing conclusions for the international journal Lung Cancer, the research team concludes, “Molecular pattern recognition of exhaled breath can correctly distinguish patients with mesothelioma from subjects with similar occupational asbestos exposure without mesothelioma, and from healthy controls. This suggests that breathprints obtained by electronic nose have diagnostic potential for mesothelioma.”
Dragonieri, S et al, “An electronic nose distinguishes exhaled breath of patients with Malignant Pleural Mesothelioma from controls”, September 14, 2011, Lung Cancer, Epub ahead of print.
Chapman, Eleanor et al, “Breath analysis in asbestos-related disorders: a review of the literature and potential future applications”, September 2010, Journal of Breath Research.