Laser-based tool could help to diagnose melanoma

High-resolution images from a laser-based tool developed at Duke University could help doctors better diagnose melanoma, a form of skin cancer.

The tool probes skin cells using two lasers to pump small amounts of energy into a suspicious mole. Scientists analyse the way the energy redistributes in the skin cells to pinpoint the microscopic locations of different skin pigments.

For the first time, scientists have the ability to identify substantial chemical differences between cancerous and healthy skin tissues, said Thomas Matthews, a Duke graduate student who helped develop the new two-laser microscopy technique.

The Duke team imaged 42 skin slices with the new tool. The images show that melanomas tend to have more eumelanin, a kind of skin pigment, than healthy tissue.

Using the amount of eumelanin as a diagnostic criterion, the team used the tool to correctly identify all 11 melanoma samples in the study. The results appear in the 23 February issue of Science Translational Medicine.

The technique will be further tested using thousands of archived skin slices. Studying old samples will verify whether the new technique can identify changes in moles that eventually did become cancerous.

Even if the technique proves, on a large scale, to be 50 per cent more accurate than a biopsy, it would prevent about 100,000 false melanoma diagnoses, said Warren S Warren, director of Duke’s Center for Molecular and Biomolecular Imaging and a chemistry professor. Warren oversaw the development of the new melanoma diagnostic tool.