Thanks to new technology being developed by Swiss scientists and already tested on patients, blowing into a portable apparatus equipped with sensors will allow for the detection of certain cancers of the head and neck, such as throat and mouth.

Scientists from the École polytechnique fédérale de Lausanne (EPFL) have created a new device capable of detecting the presence of certain cancers in the throat and mouth through a patient's breath. Early detection would lead to better treatment and a higher rate of survival and yet, according to the scientists, very few routine exams exist to detect cancer, the third leading cause of death worldwide.

Their technology, the result of international collaboration, uses sensitive and extremely precise sensors and can function just as well with a computer as with a smartphone.

The team of scientists, which includes Frédérik Loizeau, former doctoral student at EPFL, developed this apparatus capable of differentiating the breath of a healthy person and that of a sick patient based on the observation that human breath contains volatile organic compounds (VOCs) whose presence and concentration changes depending on the patient's state of health. Cancerous cells in fact produce different substances in human breath, in terms of both quantity and typology. This new tool can evaluate the composition of each breath thanks to a network of micro-sensors composed of a silicon disk 500 micrometres in diameter that is covered by a polymer and suspended by four minuscule "bridges" with integrated piezoresistors.

"There are already methods for detecting molecules called 'electronic noses' on the market. But they have a hard time analyzing very complex gases like human breath," says Nico de Rooij, who participated in the development of this technology. "Humidity in particular can disrupt the reading, leading to false positives or false negatives."

With the collaboration of the Swiss Nanoscience Institute of the University of Basel, the EPFL researchers were able to test their device on actual patients from the University Hospital of Lausanne (Centre hospitalier universitaire vaudois, CHUV) who were either sick or had undergone surgical treatment for head and neck cancer. The apparatus was able to distinguish people with cancer from those who had been operated on.

The technology, already patented, could soon be marketed.

The multiple uses for these sensors have also generated interest from the NIMS/MANA research center in Japan, another partner in the project, which just produced a prototype connected to mobile phones.

Various other domains could also benefit from this technology. Biologists at the University of Neuchatel are studying its use to analyze gases emitted by plants when they are attacked by insects or mushrooms. The ability to detect this phenomenon early on could allow farmers to react more quickly to an attack and, as a result, use less insecticide.