This tumor grows slowly from the envelope towards the nervous system, which it will compress. Most often benign and very slow growing, the tumor is sometimes discovered by chance, following a control MRI, for headaches for example. “It also happens that a meningioma is discovered following an epileptic attack. In this case, since it is he who irritates the cerebral cortex, the operation can remove epilepsy. “
What treatment?
These incidental meningiomas, discovered “by chance” during a control examination, remain stable in 50% of cases. “I am several patients for meningiomas that do not grow“recognizes Professor Raftopoulos. In these cases, there is no treatment, just control.
But if the meningioma pushes and compresses the nervous system, we’ll decide to operate on it. “The art of surgery is to remove as much of this meningioma as possible with the least possible sequelae..”
Remove the maximum, why? “To reduce the risk of recurrence. Sometimes there are even when you think you have removed everything. But complete excision, for a benign tumour, makes no sense if it induces significant deficits. Better then to leave a small residue which will eventually be treated by radiotherapy. The operation is delicate. “The most difficult thing is when a meningioma envelops the nerves. We might reach the hearing nerve, the swallowing nerve… and cause a disability. It’s a long process, a surgery lasting several hours. Peeling off the meningioma from the brain is difficult, but it’s even more difficult to peel off the tumor from the cranial nerves without damaging them.“
The neurosurgeon explains that if the residue – which is 5 to 10% of the initial tumor – tends to grow, stereotaxic radiotherapy can be performed, which burns the residue and controls the disease for an extremely prolonged period.
The tumor is analyzed
After removing the tumor, it is analyzed. “A classic analysis, under a microscope, with dyes. Then molecular biology, where we look for mutations in certain genes. A mutation of the NF2 gene is regularly observed in meningiomas. It’s interesting to know, for future gene therapies.”
A scan showing that the meningioma is aggressive will lead to closer monitoring and often radiation therapy in the weeks following surgery. “But radiation therapy has controversial effectiveness. I happened to operate several times on a patient, who had a grade 2 meningioma, which grew back several times, despite radiation therapy.“