Meningioma
Meningioma is a predominantly benign tumor that grows from the cells of the dura mater of the brain. The neoplasm grows from the arachnoid endothelium, which is the tissue surrounding the brain. Meningioma is a limited node of a slightly rounded shape, which is soldered to the dura mater. Sometimes there are also flat nodes. The size of the tumor can vary from a couple of millimeters to 15 cm.
The content of the article:
Causes of meningioma
Classification of meningioma
Symptoms of meningioma
Diagnosis of meningioma
Treatment of meningioma
Prognosis of meningioma
Meningioma
In neurology, meningioma is one of the most common tumors. This diagnosis is made in 25% of cases of all primary brain tumors. In most patients, usually only one neoplasm is detected, but there may be several of them. It is proved that meningioma is most often diagnosed in patients older than 35 years. The most characteristic age period for the formation is 40-70 years. In children, this type of tumor is extremely rare — in only 1.5% of cases.
Causes of meningioma
As a result of research, scientists have established a relationship between the appearance of a tumor and a genetic defect in chromosome 22. Scientists have also found a link between a woman’s hormonal background and the appearance of a tumor. At the same time, it is women who are most often diagnosed with meningioma. There is also a natural connection between neoplasm and breast cancer. Meningioma may increase in size during pregnancy.
Doctors identify risk factors that, in certain situations, can provoke the formation of neoplasms in the brain. These include: exposure to poisons, traumatic brain injuries, radiation exposure. Often, patients are found to have expansive meningiomas that grow in one node, while pushing apart the surrounding tissues. In rare cases, multicentric neoplasm growth is diagnosed from several foci at once.
Classification of meningioma
In neurology , it is customary to distinguish three degrees of meningioma:
I is a benign slow—growing neoplasm that does not affect the surrounding tissues. This tumor is characterized by a favorable prognosis. Patients with this degree of neoplasm practically do not relapse. It is the most common type of meningioma, since it accounts for 94.5% of all cases. Benign meningiomas are divided into nine subspecies: fibrous, meningotheliomatous, transitional, angiomatous, psammomatous, metaplastic, secretory, microcystic, with an abundance of lymphocytes.
II is an atypical tumor characterized by aggressive and very rapid growth. The prognosis for patients with this neoplasm is less favorable. In addition, there is a high risk of its recurrence. Atypical meningioma is diagnosed in 4.7% of cases.
III — a malignant tumor that grows very quickly and involves the surrounding tissues in the pathological process. After its complete removal, there is a high risk of relapse. Such a tumor is extremely rare — in 1% of cases.
Symptoms of meningioma
An asymptomatic course of the disease is possible, in which the patient does not complain about the state of health. However, without visible symptoms, the disease can proceed until the tumor increases in size. In neurology, it is customary to distinguish the cerebral and focal symptoms of meningioma. The general cerebral manifestations of the disease include:
nausea;
vomiting;
headaches;
epileptic seizures;
disorders of consciousness;
problems with the sense of smell and hearing;
visual disturbances.
Focal clinical symptoms of the disease directly depend on where the neoplasm is located. If the tumor is localized on the surface of the cerebral hemispheres, convulsive syndrome may occur in patients. In this case, hyperostosis of the cranial vault bones is also possible.
The defeat of the middle part of the frontal lobe is manifested by convulsions, muscle weakness, numbness of the extremities. As the neoplasm grows, the patient will have hemiparesis. A tumor of the base of the frontal lobe is characterized by violations of the sense of smell. If the neoplasm affects the posterior cranial fossa, there may be violations of gait, coordination of movements and auditory perception. A tumor in the area of the Turkish saddle is accompanied by visual analyzer disorders, up to loss of vision.
Diagnosis of meningioma
Diagnosis of meningioma can be difficult, because often within a couple of years the tumor grows and does not manifest itself. In this regard, patients who have nonspecific symptoms of neoplasms can easily be misdiagnosed. When the first pronounced clinical manifestations of meningioma appear, the patient is prescribed a comprehensive diagnostic examination.
In addition to neurological examination, the patient is also prescribed consultations with an ophthalmologist and an otolaryngologist. During an ophthalmological consultation, the doctor examines the patient’s visual acuity, performs ophthalmoscopy, and identifies the size of the visual fields. If the patient has severe hearing impairment, he necessarily undergoes otoscopy and threshold audiometry procedures. For accurate diagnosis, neuroimaging methods are used: CT, MRI, PET, scintigraphy, selective and non-selective cerebral angiography.
MRI
MRI is considered to be the leading diagnostic method, since it allows you to visualize in detail the vascularization of the neoplasm, determine the degree of damage to the venous sinuses and arteries, and identify the relationship between the tumor and its surrounding structures. In most meningiomas (65%), a dural tail is detected during the study, which makes it possible to more accurately identify the disease. MRI is more often used to diagnose tumors than other methods, but the method has one significant drawback — frequent cases of false negative diagnoses in the presence of hemorrhage foci and calcinitis.
ct
CT can diagnose meningioma in 90% of all cases. This technique is mainly used to demonstrate calcifications in the tumor.
PAT
Another accurate method of diagnosing neoplasms is PET, which is nevertheless not widely used because of its high cost.
Angiography
Angiography is prescribed to visualize the blood supply to the tumor. Considering that this method is invasive and also provides radiation loading, it is auxiliary. In some cases, together with selective embolization, angiography is used for preoperative preparation of the patient, and sometimes as an independent method of treatment.
Treatment of meningioma
Treatment of meningioma involves surgery and radiation therapy. Chemotherapy is not used because of its ineffectiveness, since in most cases the tumor is benign. Chemotherapy is used if other methods do not work.
The choice of treatment method depends on the following factors: the stage of the disease, the size and localization of the tumor. Usually, treatment begins with drug therapy with corticosteroid drugs, this allows you to reduce swelling of brain tissues and remove the inflammatory process. If the patient has seizures, he is prescribed anticonvulsants.
Surgical treatment
A brain meningioma is a benign tumor that has clear edges, so it can be surgically removed. With a superficial location of the neoplasm, the chances of its complete removal and subsequent recovery of the patient are very high. The operation begins with the opening of the skull, after which the neoplasm is removed. The operation also carries some risks, since after it is performed, complications may occur if the tumor has managed to affect the surrounding veins and brain tissue.
Radiation therapy
This technique is based on the fact that radiation is harmful to tumor cells. Traditionally, radiation therapy is carried out in several sessions, during which the tumor is always irradiated in the same position. Such therapy requires a lot of time. There is a high risk of complications like hair loss or radiation dermatitis. Usually this technique is chosen for treatment in the case when it is not possible to surgically remove the tumor. Due to complications and contraindications to radiation therapy, recently it has been increasingly replaced by another more innovative method of treatment – stereotactic radiation therapy.
Stereotactic radiation therapy (radiosurgery)
The main advantage of this technique over radiation therapy is that it allows you to purposefully affect the tumor from different angles. It is important that during the procedure, only the tumor receives the maximum dose of radiation, and the surrounding tissues are not injured. Another important advantage of radiosurgery is its non-invasiveness. This method of treatment is indicated in the following situations: when access to the tumor is difficult, the patient’s condition is serious, there is a high risk of complications.
In comparison with other methods of treatment, radiosurgery does not require preoperative preparation, anesthesia and long recovery after surgery. The prognosis for the patient depends on the size of the tumor. The technique is not used if the patient has been diagnosed with a tumor larger than 35 mm. In almost 100% of cases, this technique allows you to stop the growth of the tumor. In most cases, one course of treatment is enough, but sometimes a repeat course may be required. The risk of meningioma recurrence after stereotactic radiation therapy is very low. The risk of complications after this operation is much lower than with radiation therapy and surgery.
Prognosis of meningioma
The prognosis for a patient with meningioma depends on its localization, histological type and prevalence of the process. After removal of a benign meningioma, relapses usually do not occur. Nevertheless, in most cases, it is almost impossible to carry out a total removal of the neoplasm. The process of treatment and recovery of the patient is largely influenced by concomitant diseases such as diabetes mellitus, coronary artery disease, atherosclerosis. The age of the patient and the presence of previous operations on the brain are affected.
Benign meningiomas after total removal within five years recur only in 3% of all cases. The same indicator for atypical tumors is 38%. Doctors report the most unfavorable prognosis to patients with malignant neoplasms, since the risk of their recurrence after removal is 78%. As for the localization of neoplasms, a high risk of recurrence is noted in meningiomas of the wings of the main bone (60-100%).
