University of Bristol researchers have demonstrated in a clinical study that the use of a fluorescent marker would allow surgeons to more accurately spot and remove brain cancer.
The research, conducted in people with suspected glioma, was intended to investigate the use of 5-aminolevulinic acid or 5-ALA. The chemical glows pink in the presence of light.
According to the team, a fluorescent marker helps in differentiating the most aggressive cancer cells from other brain tissue. This is expected to enhance patient survival.
“Out of the 14 patients where surgeons did not see any fluorescence, seven tumours were subsequently analysed by pathology and all were found to have low-grade disease.”
University of Bristol associate professor Kathreena Kurian said: “Many patients are treated with surgery and the aim is to safely remove as much of the cancer as possible.
“We wanted to see if using a fluorescent marker could help surgeons objectively identify high-grade tumour cells during surgery, allowing them to remove as much cancer as possible while leaving normal brain tissue intact.”
During the study, 99 patients with suspected high-grade gliomas were given a 5-ALA-containing drink for consumption before undergoing surgery. Prior studies showed that 5-ALA accumulates in fast-growing cancer cells.
Study surgeons then used operating microscopes to look for fluorescent tissue while removing the brain tumours. The removed tissue was tested for accuracy in a pathology lab.
Data revealed that surgeons were able to see fluorescence in 85 patients, and 81 of these were confirmed by pathologists of having high-grade disease. One was observed to have low-grade disease and three could not be assessed.
Out of the 14 patients where surgeons did not see any fluorescence, seven tumours were subsequently analysed by pathology and all were found to have low-grade disease.
Findings from the study were presented at the 2018 National Cancer Research Institute (NCRI) Cancer Conference.
A larger study with more patients having low-grade disease is required to validate the fluorescent marker approach. The researchers intend to evaluate other types of markers for low-grade glioma cells.