Pleural mesothelioma, the cancer asbestos exposure is notorious for causing, is known to be a very challenging disease to timely detect, as symptoms do not show up until advanced stages and misdiagnosis is also quite common. Over recent years, researchers all over the world have been striving to come to the rescue of potential mesothelioma sufferers and develop effective diagnostic tools to promote early diagnosis. Undeniably, substantial progress has been made since the 1970s, when mesothelioma was first associated with asbestos exposure, and patients now benefit from a wider range of screening methods. However, since mesothelioma is so insidious and often asymptomatic, there is always room for improvement when it comes to diagnostic tools.

Recently, a group of researchers at the Ghent University Hospital and Antwerp University Hospital in Belgium have come up with a surprisingly promising breath analysis tool which can identify the disease in early stages. Furthermore, the test is non-invasive, easy to administer, fast, as well as cost-effective. The test, which was named breathomics, involves the use of spectrometric, chromatographic, and sensor techniques to detect organic molecules – the biomarkers of mesothelioma – in breath. "We believe a breathomics-based biomarker approach should be further explored to improve the follow-up and management of asbestos-exposed individuals", Sabrina Lagniau, lead researcher, wrote in the study, which was published in the Oncotarget medical journal in 2017. The test is based on multi-capillary column-ion mobility spectrometry, which can identify volatile organic compounds in the breath, and takes approximately 10 minutes to complete. "We aim to develop breath analysis as a point-of-care biomarker test that meets these requirements", Lagniau added.

Similarly to blood tests, the new breath test works by detecting tumor biomarkers, measurable substances whose presence indicates that something is not functioning properly in the body. They can refer to diseases, infections, or any other type of health problem. Nonetheless, the biomarkers this innovative test targets are those released by mesothelioma tumors in the air exhaled by the patient. Researchers found out that "exhaled breath contains valuable information on cell and tissue metabolism". It is worthy of note that the first study did not entail a clinical trial and was solely based on preexistent scientific literature. "Rigorous studies on large patient cohorts and appropriate controls will determine the clinical validity and utility of breathomics in the diagnosis of mesothelioma", the Belgian researchers stated.

The researchers behind the breath test believe that it should focus primarily on people with a history of occupational asbestos exposure, as they are most susceptible to developing pleural mesothelioma. By undergoing the breathomics screening method regularly, the potential onset of the disease could be timely detected by medical professionals. Nevertheless, the breath test can also be used as a monitoring tool for individuals who are already suffering from mesothelioma. "Cancer is a disease that affects people in every layer of society and we, scientists, have the obligation to use our knowledge on human health in exploring new ways to improve cancer management. Therefore, future studies should focus on the at-risk population, consisting of people being exposed to asbestos with a latency time of at least 20 years after exposure", lead researcher Sabrina Lagniau wrote.

Subsequently, the same Belgian researchers examined the breath samples of 66 patients belonging to the following three groups:

• 23 people who already had a pleural mesothelioma diagnosis
• 22 individuals with a history of occupational asbestos exposure, but no symptoms 
• 21 healthy participants (the control group)

The accuracy rate of the breath test was found to be 87% when telling mesothelioma patients apart from individuals exposed to asbestos, whereas the effectiveness of the breathomics method was 76% when the difference between mesothelioma sufferers and healthy people came into play.

In December 2017, they conducted another study, which yielded mixed results. When it came to differentiating people with a history of workplace asbestos exposure and those with a benign lung disease such as asbestosis from individuals with mesothelioma, the breath test showed 96% accuracy. Finally, researchers concluded that, after undergoing additional improvement, this method may become a highly reliable screening and diagnostic tool for pleural mesothelioma which could be employed on a large scale. "This method seems very promising in the early detection of diverse malignancies because exhaled breath contains valuable information on cell and tissue metabolism", they wrote.