Meningioma
Il meningiomas it's a usually benign brain tumor that interests the meninges, but it can also involve the surrounding nerve tissues through a compression action. It is worth remembering how the meninges are structured.
How are the meninges made?
The meninges are membranes that surround the brain and spinal cord. They consist of three layers, going from the inside out:
- pious mother, where the blood vessels bring nourishment to the surface of the central nervous system
- arachnoid
- dura mater, within which blood vessels feed the skull
Classification of meningiomas
The World Health Organization has classified meningiomas by identifying 15 types based on the morphology of the cells that compose them (histological subtypes):
- Grade I Benigno
- Grade II Atypical, which grows faster and can expand in the brain. If atypical, cerebral meningioma can reform more easily
- Degree III Malignant, characterized by an even faster development and more marked cellular anomalies. It has even more chances of spread and recurrence
The risk factors
Some categories of people are at greater risk of developing a meningioma, which occurs more frequently in women (2 times more than men) and in general in people between 30 and 70 years. Precisely the greater incidence in female subjects has made scientists focus the attention on the relationship between brain meningioma and hormones: estrogen, progesterone and androgen have been detected in some of these cancers, as well as its development is related to menstruation, pregnancy and breast cancer. However, it should be noted that the chances of diagnosing a malignant meningioma are 3 times higher in men than in women. In children, meningioma is a rarer possibility, although in some cases a link has been observed between this cancer in childhood and radiation exposure. ionizing. Finally, the role of the type 2 neurofibromatosis, a genetic condition that increases the risk of developing malignant or multiple meningiomas. Meningioma is not hereditary, but it can become one as a consequence of this pathology.
Meningioma: symptoms and types
Meningioma can cause symptoms such as:
- headache
- convulsions
- mood and behavior disorders
- drowsiness
- confusion
- progressive focal neurological deficit
- hearing loss or tinnitus
- vision disturbances
- muscle weakness
- nausea
- vomiting
Depending on where the meningioma is located, it is identified with a specific type, which in turn can manifest itself with characteristic symptoms:
- cavernous sinus meningioma, in the venous plexus which drains venous blood from the brain to the heart
- ponto-cerebellar angle meningioma, next to the lateral margin of the cerebellum
- meningioma of the cerebral convexity, on the brain surface just below the skull, which can lead to headaches, seizures, neurological deficits
- meningioma of the foramen magnum or foramen magnum
- intraorbital meningioma, which can cause an increase in pressure within the orbit and consequently protrusion of the eyeballs and, in severe cases, loss of vision
- intraventricular meningioma, in the cavities where the passage of cerebrospinal fluid occurs. If it is blocked, thehydrocephalus obstructive, with headache, dizziness and impaired mental functions
- meningioma of the olfactory shower, along the nerves that connect the brain and nose and allow us to perceive odors. If the compression on the nerves is intense, loss of smell and vision can occur
- parasagittal and sickle meningioma, statistically the most common, which can present with impaired thinking and memory, seizures, numbness of the lower limbs
- meningioma of the petrous rock, the part of the temporal bone in which the organs responsible for hearing are kept
- meningioma of the posterior fossa, in the posterior area of the brain. This type can cause hearing loss, balance and coordination problems
- sphenoid meningioma, near the sphenoid bone, which can manifest itself with vision problems, numbness of the face and seizures
- spinal meningioma, localized in the spine, linked to possible pain in the back and limbs
- suprasellar meningioma, in the area where the pituitary gland is located, which can cause vision problems
- meningioma of the tentorium, at the connection point between the brain and the brainstem
Meningioma: from diagnosis to surgery
It is not easy to recognize the symptoms of a brain meningioma, which can have a very slow development and is not characterized by such specific symptoms. The most used tools are the computed tomography , magnetic resonance, although sometimes the only way to get a certain diagnosis is the biopsy performed by the neurosurgeon. The time of diagnosis is very important: the younger the subject, the more positive the prognosis. Although meningioma usually does not affect life expectancy (when benign), it can change the quality of life if symptoms prove important. It is therefore important to identify the right treatment. Since cerebral meningioma typically has a precise extension, complete surgical removal is the best option. The surgery is performed with a craniotomy to access the tumor, which is removed together with the fibers that connect it to the linings of the brain and bones. Of course, the possibility of surgery must be carefully considered, based on the individual situation of the patient. If the meningioma cannot be removed surgically, the radiotherapy can be considered an alternative. Is there a drug treatment for meningioma? Actually no, even if the evolution of research has made it possible to obtain chemotherapeutic agents more aimed at treating the malignant tumor. In some cases the meningioma manifests itself with calcific or ossified elements: the calcific meningioma it is more common in the elderly and in general it does not need to be treated.