Electronic nose by IEO
A decisive step forward in the prevention of lung cancer – one of the most lethal types (it is the leading cause of death due to cancer in the world) – was presented in recent days by the IEO (European Institute of Oncology) of Milan: an “electronic nose” that allows detection of the disease in the initial phase (Stage I) when the likelihood of recovery can reach 80% (the 5-year survival rate is 54% if the disease is detected when it first appears, but only 15% of the cases are diagnosed in this phase). Because, especially in the case of lung cancer, early diagnosis makes the difference: in fact, if detected in the initial phase, a lung tumour is easily removable with a simple laparotomy (and minimal stay in hospital) and then kept under control.
What is truly extraordinary about the discovery that the IEO has developed together with Tor Vergata University of Rome, is the simplicity and the inexpensiveness of an instrument that, in the not distant future, could be at the disposal even of general practitioners for routine screening, in the same way as for glycaemia, as an exam for predisposed individuals. In fact, all it takes is a mere breath into a special container that then will be analysed by the instrument.
The electric nose is formed by a matrix of eight quartz crystals, each coated with a different metalloporphyrin, which makes it possible to detect the tumour in the initial phase in 92% of the cases. Tested on 146 individuals, 70 of whom with a diagnosis of cancer and 76 without signs of disease, the device was able to single out the breath of those who were becoming ill with lung cancer from those who instead were running no risk. The discovery, precisely owing to this precocious feature, marks a fundamental step in the development of “gas sensor arrays” (electronic noses) that, utilizing different technologies, have demonstrated being able to identify the “molecular signature” of lung cancer, that is the whole of particles produced by the tumour (VOCs or volatile organic compounds) detectable in the breath. In the whole world there are five centres directly involved with the “electronic nose” (located in the United States, China, Holland and Japan as well as Italy, but only the Milan centre has a proposal so advanced and targeted for lung cancer). Moreover, the “nose” of the IEO is the only one to have passed the examination of an Ethics Committee.
Once the initial stage of the tumour is detected, the sick individual will undergo further investigation with a low-dose spiral CT to identify its morphology and then proceed with the appropriate therapies. So early a finding of the tumour by means of the “electronic nose” could delay for some time its symptoms detectable with the classic instruments: precisely what Prof. Lorenzo Spaggiari (picture), Director of the Lung Programme and of the Division of Thoracic Surgery of the IEO, calls the “risk of discovering the tumour in a sub-radiological state.” In this case all that would be necessary is the monitoring of the tumour until its obvious radiological manifestation.
The next step in furthering early diagnosis will be a study that links the “electronic nose” to the micro-RNAs (fragments of RNA that the tumour in the process of formation may release in the blood and that foretell the disease in an early stage) to select with precision the CAT candidates within the population with a high risk of disease, that is smokers. Because heavy smokers alone – it needs to be repeated yet once again – represent 85% of those who are struck by lung cancer. With the pairing “electronic nose”/micro-RNA (miRNA) it will be possible to obtain a “synergy enhancement” for a more effective diagnosis.
A parallel study, conducted by the IEO with the Department of Veterinary Science of the State University of Milan and in collaboration with Medical Detection Dogs Italia Onlus, concerns the ability of dogs to sniff out the VOCs in urine and the hypothesis that their extraordinary sense of smell can diagnose lung cancers. The idea – not new to tell the truth, in fact going back to 1989 – even if not accompanied by published studies, is unequivocally confirmed by a long history of experiments.
With these results, together with those of many others of institutes in Italy in the various fields of medicine, the IEO, which has headquarters in Milan, puts itself at the top of world research. If we then consider the funding (public and private) markedly lower than that of foreign competitors, the extreme innovativeness of the Italian study and research centres emerges, as well as the great capability and professionalism of the researchers and of the clinicians that position our country on the cutting edge of the most advanced frontier of medicine.