Meningiomas are one of the most common intracranial and spinal tumors. and although they do not always cause symptoms, they are one of the main causes of the appearance of progressive neurological alterations.
Dr. Guillermo Montes
Neurosurgeon. Clavel Institute, Barcelona
It is considered that six out of every hundred thousand people have meningiomas, although they can be perfectly asymptomatic. It has been observed that around 2-3% of autopsies of deaths from any cause in people older than 60 years have findings of meningiomas. It is the third most frequent type of intracranial tumor (14-19% of the total), and the vast majority of its appearance occurs spontaneously without family transmission, except in hereditary diseases such as neurofibromatosis.
In most cases they are single tumors.
Usually, these are single tumors, in less than 10% of cases there is the appearance of multiple tumors, and it usually has to do with history of cranial radiation as in the treatment of childhood or juvenile cancers.
Meningiomas are not tumors of the brain or nervous tissue, but originate in the meninges, the three membranous layers that cover, protect, and nourish the brain and the rest of the central nervous system. Therefore, do not usually cause direct destruction of neural tissue except when they acquire large volumes and interfere with the correct oxygenation of the surrounding tissue due to pressure, since the vast majority are of the WHO Grade 1 benign type.
Only a small part of them present signs of aggressiveness (atypical meningiomas or grade 2), and the proportion that has a malignant behavior of infiltration and destruction of the surrounding organs is even smaller, and this type can be considered quite rare (meningosarcomas or 3rd grade).
varied symptomatology
Its symptomatology is very varied depending on the location in which they appear and on which brain area they produce compression. The most frequent age of debut and diagnosis is between the fifth and sixth decades of life. One of the most frequent symptoms is headache, which occurs when the tumor causes a lot of inflammation in the surrounding brain tissue (edema) or when it has acquired a very significant volume and causes intracranial hypertension.
If this happens, they can also occur uncontrollable vomiting in advanced cases coinciding with the headache. It is usually a headache Slow onset, but progressively increases over the weeks. They are also possible producers of epileptic seizures by pressing on the cerebral cortex.
Other times, when they press on the motor area of the brain, they can create weakness of the limbs on the opposite side of the body (hemiparesis). When they grow up in the dividing line of the two hemispheres they can affect the strength of both legs and cause urinary incontinence. If they grow close to the language area, they can cause language alterations (aphasia). Sometimes, they grow at the base of the skull, affecting the output of the olfactory nerves or the auditory nerves, and they can even grow near the optic nerves, causing loss of vision. The different nerves in charge of the senses are in locations far from each other in the skull, so it is not common to have a simultaneous affectation of them.
slow growing tumors
These tumors, being often slow-growing, if they grow in an inconspicuous area (of inconspicuous function) can give rise to pictures of cognitive or memory impairmentand even depression or alteration of behavior or personality, which are confused with neurological or psychiatric pathologies of another lineage.
For this reason, although tumors are by no means the most frequent cause of the appearance of these symptoms, they are always should have a brain imaging test at the beginning of the study of these tables since their management would be radically different. Of course, in any of the aforementioned cases, the larger the size they acquire, the greater the probability of causing symptoms and the greater their severity.
When meningiomas are found incidentally, if no growth is observed and they are not responsible for the symptoms that the patient presents, it is possible to carry out periodic controls and adopt a vigilant behavior. However, when they show signs of growth or become symptomatic, surgical excision should be considered, as it is the only potentially curative treatment.
After resection, like any tumor, they have a some risk of regrowth or recurrenceranging from 7-20% of cases in grade 1, to 50-78% in grade 3.
It has been observed that the main determinant of the probability of recurrence is the degree of initial resection. When this is maximum, at 10 years only 9% of cases have reappeared. However, when it is not possible due to localization or involvement of vital structures that could be damaged, there may be signs of regrowth in a third of the cases in the same period.
Optimism regarding survival
Survival is generally good, being in in the case of benign cases, more than 80% of cases at 5 years (especially under 40 years).
The main risk of meningiomas is not considering their diagnostic possibility when relevant neurological symptoms or headaches appear, especially if the intensity of the symptoms becomes progressively apparent over a period of days or weeks. An early diagnosis allows minimizing sequelae and optimizing the degree of tumor resection.