Seminario di G.Zonta

Il giorno 11 dicembre alle ore 14 presso l'aula 412, Giulia Zonta (University of Ferrara) terra' un seminario dal titolo

Device composed by chemoresistive sensors for colorectal cancer preventive screening

Abstract

Colorectal cancer (CRC) is a worldwide diffused pathology for both men and women. However, if promptly diagnosed, it is also one of the most curable tumor types, with a curability rate of about 90% at stage I. For this specific reason, an efficient preventive screening is fundamental to avoid its degeneration. The test currently adopted by Italian National Health Service (NHS), and in other conuntries, as mass population screening is fecal occult blood test (FOBT). In Ferrara, the immunochemical version of this test (FIT) is performed since 2005 every two years on subjects from 50 to 69 years old and shows a huge percentage of false positives (about 65% according to the analyzed data). FIT positives are then invited to undergo colonoscopy. The device SCENT A1 (patented in Italy, UK and Germany), is capable of performing a non-invasive analysis of fecal samples, recognizing the tumor presence by their odor. Their odor is in fact different from fecal samples of healthy subject, due to tumor biomarker contamination. These biomarkers are volatile organic compound produced by tumor-affected cells by mechanisms as peroxidation or metabolic alterations. The clinical validation outcomes of a protocol that involved University of Ferrara, AUSL-FE, Ospedale S. Anna (Cona) and SCENT S.r.l., lasted for about three years (May 2016-July 2019), are presented here, alongside with a description of the device structure and functioning, chemoresistive sensors mechanisms and a detailed delineation of clinical validation protocol lines. More than 500 subjects, resulted positives to FIT, have adhered to the study and colonoscopy has been used as gold-standard. Each patient brought a sample of frozen feces to be analyzed by SCENT A1, before colonoscopy preparation. Data have been analyzed with an algorithm, specifically realized by employing techniques as principal component analysis and support vector machine. Sensitivity and specificity of SCENT A1 resulted to be 84,1% and 82,4% respectively, showing the high potentialities of this test, if employed on FIT-positives, of reducing of about two thirds the FIT false positives and so, non-operative colonoscopies (performed on healthy subjects).