A blood test could one day determine whether a brain tumour requires treatment, research suggests.
The malignant masses vary in severity, with up to 85% of the tumours considered low-grade. These do not always become cancerous, making high-risk surgery and aggressive chemotherapy unnecessary.
Treatment for meningioma – the most common brain tumour among adults – is somewhat muddled, with certain patients put on "watch and wait" while others endure therapies to remove the mass.
Scientists from the the University of Plymouth have discovered that higher levels of the blood protein FBLN2 are detectable in grade II meningiomas, which often become cancerous and require treatment to prevent them spreading.
The "exciting breakthrough" could spare some patients "the ordeal of neurosurgery", according to one expert.
"In this study, we identified FBLN2 as a novel biomarker that can distinguish grade II from grade I meningiomas," said lead author Professor Oliver Hanemann.
"Higher levels of this biomarker were found in tumour samples from grade II meningioma compared with the grade I form.
"We also showed higher levels of FBLN2 can be detected in blood samples from grade II meningioma patients, compared to those from grade I meningioma patients.
"The identification of FBLN2 as a biomarker for meningioma has significant potential to improve the diagnosis, treatment, prognosis and follow-up of meningiomas."
The scientists analysed 87 grade I and 91 grade II meningioma cell, tissue and plasma samples, with the grades differentiated according to the World Health Organization's Classification of the Tumours of the Central Nervous System 2016 edition.
The team found FBLN2 was "differentially expressed" between the two grades' cells, with levels also "significantly higher" in grade II tissue and plasma samples.
"This study suggests elevated Fibulin-2 [FBLN2] might be a novel grade II meningioma biomarker, when differentiating them from the grade I tumours," the scientists wrote in the International Journal of Molecular Sciences.
"The trend of Fibulin-2 expression observed in plasma may serve as a useful non-invasive biomarker."
FBLN2 has not previously been linked to meningioma development, but was known to be involved in other forms of cancer, like those affecting the lungs, liver, breasts and pancreas.
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By identifying grade I tumours, lower-risk patients could be spared surgery, chemotherapy or radiotherapy.
One who knows the impact of neurosurgery all too well is Victoria Bradley.
Bradley, 50, from Plymouth, went under the knife after being diagnosed with a meningioma in 2017.
The former overseas holiday representative was forced to give up work when the operation led to debilitating side effects, including seizures.
"My diagnosis and operation has changed everything about my life," she said.
"Going through neurosurgery is a massive thing. I live in constant fear, no longer feel comfortable going out on my own and always, always, have an emergency alarm with me to call help in case I have a seizure.
"It is absolutely wonderful and incredible to think, one day, patients like me might not have to go through surgery."
There is "no consensus on the optimum management of grade II meningiomas", wrote the Plymouth scientists.
"This is an exciting breakthrough which could see patients spared the ordeal of neurosurgery at what is already likely to be one of the most difficult times of their life," said Hugh Adams, spokesman for Brain Tumour Research, which funded the study.
"In the UK, 16,000 people are diagnosed with a brain tumour each year, and more children and adults under the age of 40 are lost to brain tumours than any other cancer."
This comes after the Plymouth scientists found the protein GATA may also be a reliable blood marker for high-grade meningiomas.
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