A chemical that highlights tumor cells has been used by surgeons to help spot and safely remove brain cancer in a trial presented at the 2018 NCRI Cancer Conference. The research was carried out with patients who had suspected glioma, the disease that killed Dame Tessa Jowell, and the most common form of brain cancer . Treatment usually involves surgery to remove as much of the cancer as possible, but it can be challenging for surgeons to identify all of the cancer cells while avoiding healthy brain tissue.
Researchers say that using the fluorescent marker helps surgeons to distinguish the most aggressive cancer cells from other brain tissue and they hope this will ultimately improve patient survival.
Dr. Kurian explained: "Gliomas are difficult to treat with survival times, often measured in months rather than years, and many patients are treated with surgery and the aim is to safely remove as much of cancer as possible. is passed on to a pathologist who examines the cells under a microscope to see if they are 'high-grade', fast-growing cells, or 'low-grade' slower growing cells. , based on that diagnosis.
"We wanted to see if a fluorescent marker could help surgeons objectively identify high-grade tumor cells during surgery, allowing them to remove as much cancer as possible while leaving normal brain tissue intact."
The researchers used a compound called 5-aminolevulinic acid or 5-ALA, which glows pink when a light is shone on it. Previous research shows that, when consumed, 5-ALA accumulates in fast-growing cancer cells and this means that they act as a fluorescent marker of high-grade cells. Fast-growing cancer cells and this means it can act as a fluorescent marker of high-grade cells.
The study involved patients with suspected high-grade gliomas treated at the Royal Liverpool Hospital, Kings College Hospital in London or Addenbrooke's Hospital in Cambridge, UK. They were aged between 23 and 77 years, with an average (median) age of 59 years. Before surgery to remove their brain tumors, each patient was given a drink containing 5-ALA.
A total of 99 patients received the 5-ALA marker and could be assessed for signs of fluorescence. During their operations, surgeons reported seeing fluorescence in 85 patients and 81 of these were subsequently confirmed by pathologists to have high-grade disease, one was found to have low-grade disease and three could not be assessed.high-grade disease, one was found to have low-grade disease and three could not be assessed.
In the 14 patients where the surgeons did not see any fluorescence, only seven tumours could be evaluated by pathology but in these cases, low-grade disease was confirmed.tumours could be subsequently evaluated by pathology but in all these cases, low-grade disease was confirmed.
"The advantage of this technique is that it may highlight more rapidly high-grade disease within a tumor during neurosurgery. What this means is that more of the tumor can be removed more safely and with more complications, and that's better for the patient." tumor during neurosurgery. What this means is that more of the tumour can be removed more safely and with fewer complications, and that's better for the patient."
Next steps could include testing the 5-ALA in children with brain tumors, or to help surgeons distinguish between tumour tissue and scar tissue in patients whose brain cancers have recurred following treatment.tumours, or to help surgeons distinguish between tumour tissue and scar tissue in adult patients whose brain cancers have recurred following treatment.
"The benefit of using a fluorescent marker is that it helps neurosurgeons see more accurately where the high-grade cancer is within the brain , in real time. In treating cancer, we are trying to improve survival by tailoring treatments to each individual patient. technique provides on-the-spot information to help surgeons tailor the operation according to the location, size and grade of the tumor.
"We know that patients who have near total removal of their tumor have better outcomes, so we are optimistic that, in the Long-term, these new data will help to increase survival times for glioma patients . "