Raman spectroscopy tool helps facilitate earlier skin cancer diagnosis
Vancouver, British Columbia — Identifying the biochemical composition of moles rapidly with Raman spectroscopy may help dermatologists and general practitioners to diagnosis skin cancers.
"I view this as being potentially complementary to other (dermoscopy and confocal microscopy) technologies," says Dr. Lui, who is also professor and chairman, department of dermatology and skin science, University of British Columbia. "It is relying on a completely different way of analyzing skin lesions."
Dr. Lui, one of the investigators of this technology, explored the efficacy of Raman spectroscopy in an analysis of 1,000 lesions.
In preliminary data published in 2008, Dr. Lui and colleagues Haishan Zeng, Ph.D., and David McLean, M.D., observed 289 skin cancers and benign skin lesions, and found that skin cancers could be distinguished from benign skin lesions, with a sensitivity of 91 percent and specificity of 75 percent. Malignant melanoma could be distinguished from benign pigmented lesions, with a sensitivity of 97 percent and a specificity of 78 percent.
"We have taken volunteer subjects with (skin) cancer and without (skin) cancer, and we measure their skin lesions," Dr. Lui says. "It appears those with skin cancer will have a difference in the composition of the skin and that is detectable by Raman spectroscopy."
Raman spectroscopy is an approach to biochemically analyzing what is in the skin, Dr. Lui says. The Verisante Aura works by shining light on the skin, capturing information, and then analyzing the information on a computer. The technology is searching for specific fingerprint biomarkers, and it has the ability to do this in one second.
Raman spectroscopy is very sensitive to chemical composition; thus, it is able to detect variations in the composition and amount of certain materials in the skin, Dr. Lui says. Confocal microscopy or dermoscopy, by contrast, rely on the visual and structural appearance of lesions, he says.
Still, Dr. Lui says the application of Raman spectroscopy will not exclude the use of other technologies to diagnose skin cancers, but rather serves as a different option for analyzing skin lesions.
The previous limitation of using Raman spectroscopy in medicine has been a weak spectral signal and lengthy periods of time to acquire data, Dr. Lui says. This has been overcome with a rapid acquisition spectrometer system within the commercial device.
"In the past, to collect Raman spectra from the skin, the patient would have had to sit still for 20 minutes, and that is not practical," he says. "But now it's possible to acquire this signal within seconds, and that's been the breakthrough."