Laser-based breast cancer test faces human trials

Ashley N. Rice, ashley.rice@photonics.com

A laser diagnostic test that could lead to an instant diagnosis of breast cancer at the time of a mammogram will for the first time be evaluated using excised human breast tissue and lymph nodes.

Currently, a follow-up needle biopsy is required when a mammogram picks up abnormalities. About 70-90 percent of these tests come back negative, but not before a nervous wait for results.

The new laser technique, developed at the Science and Technology Facilities Council (STFC), could eliminate the need for a second hospital visit and the anxiety of waiting for the results because it can be implemented at the same time as the mammogram. The method, known as spatially offset Raman spectroscopy (SORS), uses a laser to pinpoint objects deep beneath the skin – without an incision.

Scientists work on the SORS (spatially offset Raman spectroscopy) technique at the Science and Technology Facilities Council’s Central Laser Facility in Oxfordshire, England. Courtesy of STFC.

“This technique, if applied at mammography, could have a huge impact on those 75,000 patients a year in the UK having to return for additional biopsies, with associated anxiety, when they are found to have nothing wrong,” said lead scientist Nicholas Stone of the University of Exeter.

The test measures signatures obtained as the laser light passes through the small calcifications found in breast tissue to determine whether benign or cancerous tissue is present.

Doctoral student Marleen Kerssens – funded by STFC’s Biomedical Network and the Gloucestershire Hospitals NHS Foundation Trust – conducted tests on pork to prove that the same concept could detect whether shadows picked up on mammograms were benign or malignant. Now, under a grant from the Engineering and Physical Sciences Research Council (EPSRC), she and her colleagues hope to optimize the technique’s sensitivity and penetration depth and, for the first time, evaluate its performance on human breast tissue that has been removed during an operation.

“I am really pleased this line of research can be continued with the support of EPSRC,” Kerssens said. “It is an exciting field of research, and translation of the SORS technique to a clinical setting has the potential to reduce the amount of false positives and therefore reduce patient anxiety.”

It will be a decade before the test can be routinely used in hospitals, the team said.

“It is very gratifying to see this technology, originally developed on our large facilities in the Central Laser Facility, being applied in so many different ways that will have such an impact on society,” said professor Pavel Matousek, inventor of the technique. “As well as developing it for future breast cancer diagnosis and for detecting counterfeit drugs, we expect, in the future, to see the technology at airports scanning liquid explosives. This support from EPSRC enables us to keep driving this technique forward, for the timeliest benefit to both individuals and the health service.”