The headquarters of the rectorate of the Politecnico di Milano
A single urine sample is enough: then, to find prostate cancer – that much frequently diagnosed among men (18,5%) – does all the electronic nose, no biopsies. The project has been talked about for about ten years. That is, since when a search for theHumanitas Institute of Milan, in collaboration with the Military Veterinary Center of Grosseto, revealed how well trained dogs were able to recognize this neoplasm by smelling the urine of sick people. Today, after a long process of research, Humanitas e Politecnico di Milano, by copying the sense of smell of our four-legged friends, they have developed an experimental prototype, born in the “Diag-Nose” project, which regularly identifies the presence of cancer by recognizing specific volatile molecules contained in the urine. There are two great advantages of the method: the fact that it is not invasive, unlike a biopsy, today the elective test for detecting cancer; and the greater accuracy of the diagnostic result. If in fact the biopsy has a rather high false negative rate in early stage tumors, given the small portion of the organ taken, the electronic nose correctly identifies the presence of the tumor in sick patients in 85.2% of cases and “results correctly negative in healthy patients in 79.1% of cases». In total, the hospital and the university explain in a note, «the accuracy, or the ability to make a correct diagnosis, whether negative or positive, is 82.1%. If we consider only men over the age of 45, the age group most affected by the disease, but also the most difficult to diagnose, the accuracy stands at 81%.
In short, it could be a turning point for the disease, which could be easily detected at an early stage and, therefore, treated with more chances of recovery. The study, published in the scientific journal International Journal of Urologywas developed between the Humanitas offices in Rozzano (Milan) and Castellanza (Varese), ed involved 174 people, divided into two groups: 88 patients with prostate cancer, and 86 people in the defined “control” group, made up of female subjects or men of different ages but unfamiliar with the disease and with visits and tests (among which the Psa) negative. A urine sample was then collected for each person and analyzed in the laboratories of the Department of Materials Chemistry and Chemical Engineering of the Polytechnic. «Prostate biopsy is today the gold standard for the diagnosis of cancer of this gland – says the promoter of the study, Gianluigi Taverna, head of the Urology unit of Humanitas Mater Domini of Castellanza and researcher -. Despite the greater precision that today the exam has achieved thanks to the use of magnetic resonance images in guiding tissue sampling, the tumor detection rate reaches a maximum of 48.5%. A significantly lower percentage than that of the electronic nose which, in addition to greater diagnostic accuracy, would limit the discomfort and complications for the patient”.
As mentioned, the electronic nose is a prototype born from the reproduction of the canine sense of smell, created thanks to a series of sensors capable of analyzing the volatile substances released into the air by urine samples. «As with dogs, the electronic nose also went through a training phase, conducted on 530 people, which allowed engineers and other experts from the Milan Polytechnic, among them Professor Laura Capelli and Dr. Carmen Bax, to refine the analysis parameters and to teach the device to distinguish urine samples», explains Fabio Grizzi, researcher at Irccs Humanitas, where he is also responsible for the histology service. For her part, Laura Capelli defines the Diag-Nose project «a beautiful example of the results that can be obtained with a multidisciplinary and close-knit team. In addition to having won the first “Disruptive Innovation” prize in the “S2P” competition promoted by Politecnico, PoliHub and Deloitte in 2019, today the project has received an important Poc loan from a Venture Capital fund for the validation of the machine».
Now a concrete application of the research is expected: «For the electronic nose to actually become part of daily clinical practice, further large-scale studies will be needed. The next step is to validate it by involving international clinical institutes,” they conclude Tavern and Grizzi.