Improved scanning techniques may help clinicians diagnose esophageal cancer at an earlier stage, according to a study published in the journal Nature Medicine (2010 Apr 11 [Epub ahead of print]).
Scientists in the Biomedical Imaging and Spectroscopy Laboratory (BISL) at Beth Israel Deaconess Medical Center (BIDMC) developed the novel technique, called endoscopic polarized scanning spectroscopy (EPSS), for the early detection of dysplasia in patients with Barrett’s esophagus. The new EPSS instrument uses light-scattering spectroscopy to enable the endoscopist to more thoroughly search for precancerous changes that occur on the cellular level.
“The detection of the signal related to precancerous epithelial cellular changes is made possible through the use of polarized light,” explains Perelman. “Since light reflected from sub-epithelial tissue will become ‘depolarized,’ while light that is backscattered from epithelial cells will preserve its polarization, the technique of polarization subtraction – or polarized light scattering spectroscopy – retains and conveys only the diagnostically important information.”
In pilot test in a clinical setting, the endoscopist was able to use the EPSS tool during biopsies to successfully detect and map sites of numerous invisible precancerous cancers that would have otherwise been missed using the current biopsy standards. “When used to guide the endoscopist, EPSS appears to not only help to avoid unnecessary biopsies, but also to help the endoscopist to locate suspicious dysplastic areas that might otherwise be missed,” said Lev Perelman, PhD, Director of the BISL at BIDMC and Associate Professor of Obstetrics, Gynecology, and Reproductive Biology at Harvard Medical School.