It is a tumor that forms in the membranes that cover the brain and spinal cord just inside the skull.
Specifically, tumors are formed in the three layers of membranes called meninges, hence the name. These tumors tend to be slow growing. Up to 90% benign (not cancerous).
Most meningiomas occur in the brain. But they can also grow in the parts of the spinal cord.
Frequently, meningiomas do not cause symptoms and do not require immediate treatment. But the growth of benign meningiomas can cause serious problems. In some cases, growth can be fatal.
Meningiomas are the most common type of tumor that originates in the center of the nervous system. They occur more frequently more in women than in men. Some meningiomas are classified as atypical. These are not considered benign or malignant (cancerous). But they can become malignant.
A small number of meningiomas are cancerous. They tend to grow quickly. They can also spread to other parts of the brain and beyond, often to the lungs.
Causes and risk factors of Meningioma
The causes of meningioma are not well known. However, there are two known risk factors.
- Exposure to radiation.
- Neurofibromatosis type 2, a genetic disease.
Meningiomas have been found in places where the skull has suffered fractures. They have also been found in places where the surrounding membrane has been healed.
Some research suggests a link between meningiomas and the hormone progesterone. Middle-aged women are more than twice as likely as men to develop a meningioma. Most meningiomas occur between the ages of 30 years to 70 years. With very rare appearance in children.
What symptoms do they produce?
Because most meningiomas grow very slowly, the symptoms often develop gradually. The most common symptoms include:
- Blurry vision.
- Weakness in the arms or legs.
- Speech problems
The diagnosis of meningiomas
Meningiomas are rarely diagnosed before causing symptoms.
If the symptoms indicate the possibility of a tumor, the doctor may order a scan in the brain: MRI and / or a CT scan. These will allow the doctor to locate the meningioma and determine its size.
A biopsy can sometimes be performed, where the surgeon removes part or all of the tumor to determine if it is benign or malignant.