We read the interesting article by De Felice et al (Gut 2006;55:1436–1439) which suggested oral light reflectance as a new clinical marker in hereditary non-polyposis colorectal cancer (HNPCC) carriers, which could be used in first level colorectal cancer (CRC) population screening programmes. Briefly, the oral mucosa of the HNPCC subjects showed significantly lower reflectance values than those of controls at 590–700 nm wavelengths, allowing a 100% accuracy in the discrimination between HNPCC carriers and controls.

With the aim of validating this new marker in identifying susceptibility to CRC, we carried …