Chemoresistive sensors for colorectal cancer preventive screening through fecal odor: Double-blind approach

Colorectal cancer screening is fundamental to decreased mortality related to the target disease. This pathology is diffused worldwide for both men and women and its curability rate, when identified at stage I, is up to 90%. Fecal occult blood test is currently the methodology adopted in many countries as a screening on population, but it shows a very high percentage of false positives, leading to non-operative colonoscopies performed on people who are often elderly and already debilitated. The use of an economic and easy-to-use method alongside fecal occult blood test would improve effectiveness of the screening. Here, the results so far obtained in the clinical validation protocol, started in May 2016, using a patented device with a core of chemoresistive gas sensors, are shown. The device can identify the difference between the fecal exhalation odor of two categories of subjects: healthy and those affected by high-risk adenomas or tumors. Moreover, further calibration of the instrument for the recognition of low-risk adenomas is on-going. The tests are compared to fecal occult blood test positives and colonoscopy results. In this work the most recent results as well as improvements in screening method are presented, useful for future large-scale production of the device.