Death for tumors is a worldwide health problem, with colorectal cancer (CRC) in particular showing to be one of the malignant tumors with the highest incidence for both genders, and with high mortality rate if not treated in time. To gain advantage on the neoplasia, and being able to identify and remove CRC in his benignant stage, pre-screening protocols like fecal occult blood test (FOBT) have been developed, and high interest from the scientific community have been shown on electronic noses, able to detect particular tumor markers secreted from cancer cells, different from blood (which may...