Colon Cancer Diagnostic Technique Uses Biomedical Optics

A colorectal cancer diagnostic technique has a high enough sensitivity that it could potentially be as, or more successful than a colonoscopy in screening for colon cancer.

The technique uses optical technology, called low-coherence enhanced backscattering (LEBS) spectroscopy, to analyze tissue samples taken from the base of the rectum. Light is shone on the tissue, scatters, and some of that light bounces back to sensors in the probe. A computer analyzes the pattern of light scattering, looking for the "fingerprint” of carcinogenesis in the nanoarchitecture of the cells. This enables recognition of cancer prior to histological evidence.

Vadim Backman, professor of biomedical engineering at the McCormick School of Engineering and Applied Science at Northwestern University (Evanston, IL, USA) and colleagues obtained biopsies from patients undergoing colonoscopies and found that LEBS could detect the presence of growths elsewhere in the colon even though it only analyzed tissue from the base of the rectum.

"If you have a precancerous lesion in one part of the colon,” said Prof. Backman, "even tissue that looks normal and is located far from the lesion or polyp will have molecular and other kinds of changes. It's the biological phenomenon called the ‘field effect.' No one can detect these changes earlier than we can.”

Recent clinical trials showed that the new colon cancer screening technique has a high enough sensitivity that it could potentially used in screening for colon cancer. The clinical trials were conducted in collaboration with Hemant Roy, M.D., director of gastroenterology research at NorthShore University HealthSystem (Evanston, IL, USA).

The study provides a proof of concept that this sort of analysis could be a minimally intrusive colon cancer screening technique. Further studies with a compatible fiberoptic probe are under way for multicenter clinical validation.

The results of this study were published in the journal Cancer Research on May 15, 2009.

Related Links:
McCormick School of Engineering and Applied Science at Northwestern University
NorthShore University HealthSystem