Novel Biophotonics Methodology for Colon Cancer Screening

Background and Significance highlights the impracticality to provide total colonic evaluation for the entire population. Risk-stratification via exploitation of the "field effect" is an attractive approach. However, all existing methodologies (e.g FOBT, fecal DNA, flexible sigmoidoscopy) are clearly suboptimal underscoring the need for novel tools for identifying the field effect.

1. We have developed ELF/LEBS for depth-selective (from ~30 to hundreds of microns) spectroscopic assessment of living tissue. 2) We tested these novel techniques in two animal models of CRC (the AOM-treated rat and MIN-mouse) and in human subjects (n=190). We demonstrated that ELF/LEBS has the potential to detect precancerous changes in the colon at a time point that precedes the formation of adenomas and other histological/molecular markers of CRC. 3) We demonstrated that rectal ELF/LEBS can detect field effect alterations in histologically normal rectal tissue changes due to the presence of adenomas anywhere in the colon. In our pilot studies, the diagnostic accuracy of rectal ELF/LEBS far exceeded any other currently known markers of CRC. Therefore, assaying ELF/LEBS in the rectum has the potential to provide accurate risk-stratification for colon carcinogenesis without the need for bowel preparation and colonoscopy. 4) We have developed prototypes of ELF and LEBS fiber-optics probes for in vivo use.