A simple breath analysis could be used for colorectal cancer screening, according to researchers at the University Aldo Moro of Bari. Cancer tissue has different metabolism compared to normal healthy cells and produces some substances that can be detected in the breath of these patients.
The research team collected exhaled breath from 37 patients with colorectal cancer and 41 healthy controls, which was processed offline to evaluate the volatile organic compound (VOC) profile. VOCs of interest had been identified and selected, and VOC patterns able to discriminate patients from controls set up. A probabilistic neural network (PNN) was used to identify the pattern of VOCs that better discriminated between the two groups.
Results showed that patients with colorectal cancer have a different selective VOC pattern compared with healthy controls, based on analysis of 15 of 58 specific compounds in exhaled breath samples. Application of a PNN to a pattern of the 15 compounds showed a discriminant performance with a sensitivity of 86%, a specificity of 83%, and an accuracy of 85%. The accuracy of PNN analysis was confirmed in the validation phase on a further 25 subjects; the model correctly assigned 19 patients, giving an overall accuracy of 76%.
“The technique of breath sampling is very easy and non-invasive, although the method is still in the early phase of development,” notes study leader Donato F. Altomare, M.D., of the department of emergency and organ transplantation at the university. “Our study’s findings provide further support for the value of breath testing as a screening tool.”
The study, called “Exhaled volatile organic compounds identify patients with colorectal cancer”, was published today in the British Journal of Surgery. It is part of the “Improving Outcomes in Gastrointestinal Cancer” supplement.