A new laser-based technology could make brain tumour surgery much more accurate, according to US research.

Scientists from the University of Michigan Medical School and Harvard University used an approach called Stimulated Ramen Scattering (SRS) microscopy to find microscopic areas of tumour cells in brain tissue of live mice.

The technique needs to be tested in clinical trials, but could one day help surgeons to better distinguish between cancer tissue and healthy tissue.

This could reduce the chance of leaving behind any cancerous cells that could lead to the patient's tumour returning.

In the study, published in the journal Science Translational Medicine, the researchers also showed that the same process was possible in tissue taken from a patient with glioblastoma multiforme, one of the most common types of brain tumour.

Surgery is often the most effective treatment for this tumour. But because of the difficulty in spotting tumour edges, only around one quarter of patients whose tumour could be completely removed by surgery actually have their whole tumour removed.

The team say they are now working to develop SRS microscopy for use in an operation before testing it in a clinical trial.

Dr Daniel Orringer, from the University of Michigan, said: "Though brain tumour surgery has advanced in many ways, survival for many patients is still poor, in part because surgeons can't be sure that they've removed all tumour tissue before the operation is over.

"We need better tools for visualising tumours during surgery, and SRS microscopy is highly promising. With SRS, we can see something that's invisible through conventional surgical microscopy."

The study marks the first time that SRS microscopy has been used to see the "margin" of a tumour, or the boundary area where cancer cells infiltrate among normal cells. This is the hardest area for a surgeon to operate on, particularly when a tumour has invaded a region with an important function.

The results suggest that the technique can identify brain tumour cells with remarkable accuracy, by detecting the differences between the signal given off by the dense cellular structure of tumour tissue and healthy grey and white matter.

Dr Colin Watts, a Cancer Research UK brain tumour expert at the University of Cambridge, said: "It needs to be tested in a clinical trial, but this technique could be an exciting development in visualising tumour tissue, which is the first step in enhancing removal of disease.

"This technique is particularly exciting because it has the potential for helping us to remove tissue at the tumour/brain interface from where recurrent disease can emerge."

He also said that it will be interesting to see if SRS microscopy could be used in tumours that come back after treatment, and stressed that it is crucial to ensure that the technique does not compromise patient safety.

Source: CRUK