Brain tumors

According to various sources, brain tumors account for 2-8.6% of all human neoplasms. Among organic diseases of the central nervous system, tumors account for 4.2-4.4%. The number of newly diagnosed CNS tumors increases annually by 1-2%. At the same time, the mortality rate due to brain tumors in adults ranks 3-5th among all causes of death. In children, mortality due to the development of an oncological process of the central nervous system ranks 2nd after diseases of the hematopoietic and lymphatic systems.

Epidemiology

In Ukraine, the incidence of brain tumors in men is 10.2 per 100,000 of the population. Among women, this figure is 7.6 per 100,000. In the USA, the incidence of brain tumors among men reaches 12.2 per 100,000, and among women - 11 per 100,000 of the population. The number of brain tumors in women aged 40-50 is 1.5 - 1.8 times higher than in men. Men are predominantly affected by glial tumors, while women are more likely to have meningiomas and neurinomas.

Distribution of neoplasms by histological structure largely depends on the average age of the patients in the study sample. Thus, in adults, 40-45% of primary tumors are gliomas, 18-20% are meningiomas, 8% are neurinomas of the VIII nerve, 6-8% are pituitary adenomas. In children, gliomas account for 75% of all tumors; meningiomas - 4%, while neurinomas and adenomas are extremely rare. In patients over 70 years of age, 40% of brain tumors are meningiomas.

Recently, there has been a tendency towards an increase in the incidence of metastatic brain tumors of this type.

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Causes brain tumors

The development of brain tumors, like any other localization, is based on a persistent violation of the integrity of the genetic apparatus of the cell, primarily those parts that are responsible for the control of initiation and progression of the cell cycle. As a rule, these are genes encoding protein factors that form the basis of the mechanism of cell division progression (Hb, E2F, cyclins and cyclin-dependent protein kinases), signal transduction proteins (for example, the Ras cascade), growth factors (for example, PDGF) and their receptors, as well as factors that inhibit the development of the cell cycle and activate cascades of apoptotic elimination of the cell, while defects in loci associated with the system of regulation of cell cycle progression lead to hyperexpression of mitotic activity promoters or to the appearance of new persistent pathological forms of promitotic factors with increased functional activity. Whereas damage to the genes of the apoptotic system in the context of oncogenesis is of the nature of loss.

Currently, data have appeared that allow us to assume that primary genetic damage occurs in cells with active expression of the cell cycle regulation apparatus, i.e. in mitotically active cells. Increased activity of the mitotic apparatus of the cell leads to its division, and genetic information is preserved in the tissue, while increased apoptotic activity leads to the elimination of the cell and the destruction of all deviations of the cellular genome. But at the same time, specialized tissue progenitors, tissue stem cells can remain in a state between apoptosis and mitosis for a long time, which opens up the possibility of gradual degeneration of genetic loci of both the mitotic and apoptotic systems with the possibility of transmitting emerging defects to subsequent cellular generations.

An important condition for the transition of a proliferating cell from the category of those with increased mystical activity to those with uncontrolled mitotic activity is the gradual accumulation of a number of mutational changes in the genome of the cell line. Thus, the development of astrocytic glioma and its degeneration into a malignant form - glioblastoma - is accompanied by the accumulation of mutational changes in the genome of tumor cells. It has now been established that mutations in chromosomes 1, 6, Er, lGq, lip, 13q, 14, 17p, 18, 19q, 22q are the key moment in the emergence and progression of the main types of brain tumors.

Mutational degeneration of genetic loci can occur for various reasons. It should be noted that some of them can have a direct damaging effect on the genome of brain cells. Another group consists of factors that indirectly increase the transcriptional load on the specified genes or reduce the activity of the genetic reparation system.

In sum, the combination of several negative factors against the background of an innate predisposition, which can be expressed in various genetic deviations, leads to a violation of the integrity of the genetic information of a mitotically active cell, which is the primary event on the path to oncogenic degeneration. The imbalance of the system of genetic transcription, reparation and replication, which inevitably occurs in this case, increases the vulnerability of the genome of the cell clone, which increases the likelihood of subsequent mutational events.

Among the unfavorable factors in this regard, it is necessary to highlight ionizing radiation, electromagnetic fields, pesticides and other factors of chemical pollution of the environment.

Of great importance is the carriage of oncogenic viruses that can provoke or promote the progression of the described processes. These include Epstein-Barr viruses, human papillomaviruses (types 16 and 18), HIV, etc.

Bad habits, as well as the "dietary" factor, have long been considered a group of classic factors that increase the risk of developing cancer. In this regard, brain tumors are no exception.

At present, the influence of a previous TBI on the possible development of a brain tumor should be considered largely hypothetical, since the corresponding temporary combination of both brain pathologies is extremely rare and is classified as an accidental finding.

Given the greater predisposition of representatives of different sexes to the occurrence of certain types of brain tumors (for example, meningiomas are more common in women), it is advisable to consider the influence of sex hormones in progression and, possibly, in increasing the likelihood of manifestation or even the occurrence of primary tumor foci.

Finally, having close relatives with tumors of the nervous system or diseases such as Recklinghausen's disease increases the risk of developing a brain tumor.

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Symptoms brain tumors

From a pathogenetic point of view, the primary significance and development of clinical symptoms is the increase in tumor volume, which leads to the direct and indirect development of increased intracranial pressure syndrome and the entire range of focal symptoms.

The formation of hypertensive syndrome occurs for three reasons. Firstly, the growth of the tumor focus leads to an increase in the volume of the tissue component in the cranial cavity. Secondly, with a certain location of the tumor, the outflow of cerebrospinal fluid may be disrupted, which leads to an increase in its volume in the cavities of the ventricular system.

And finally, thirdly, expansive tumor growth in certain cases can cause compression of the surrounding brain tissue, including vessels of various calibers, which determines its ischemia, decreased ATP production, disruption of the ATP-dependent ion exchangers that maintain a normal balance of ions between tissue compartments (intracellular environment, intercellular space, vascular bed). The latter is accompanied by an increase in the osmolality of the extravascular environment and accumulation of water in ischemic foci of brain tissue. The rapid development of edema-swelling of brain tissue, initiated at the periphery of the tumor node, can be the main factor in the further spread of this process and the involvement of increasingly larger areas of the brain.

Compression of brain areas immediately adjacent to the tumor focus leads to the development of focal symptoms. Compression of brain tissue areas located at some distance from the tumor focus, under the influence of the spreading process of edema-swelling, ischemia or as a result of tumor growth, leads to the development of symptoms at a distance. In the most advanced cases, conditions are created for the dislocation of brain tissue and the formation of wedging syndromes.

Local compression of brain tissue or increased intracranial pressure and irritation of the receptors of the meninges become possible due to the constancy of the volume of the cranial cavity. According to the Monroe-Kelly doctrine, a change in the volume of one of the three components of the cranial cavity contents (tissue, blood, cerebrospinal fluid) occurs due to a decrease in the volume of the other two. Tumor growth primarily leads to a local decrease in blood flow and is accompanied by a decrease in the volume of cerebrospinal fluid in the cranial cavity. A decrease in the volume of blood in the cranial cavity has significant consequences, as a rule, aggravating the perfusion situation in the brain tissue. Given the mechanism of development of edema-swelling of the brain, it can be predicted that the state of compensation will sooner or later be disrupted and this will lead to the emergence of a vicious circle: ischemia - edema - increased tissue pressure - ischemia.

The described pathogenetic features of the development of the tumor process explain, on the one hand, the possibility of long-term tumor growth in functionally inert areas of the brain in the absence of pronounced symptoms, and on the other hand, the presence of brain tumors, which, even with small sizes and a limited growth period, give pronounced clinical symptoms.

In clinical terms, there are general cerebral and focal symptoms of a brain tumor that arise in connection with the development of a brain tumor.

The most important and one of the earliest symptoms of intracranial hypertension development due to tumor growth is headache. This symptom is observed in 92% of patients with subtentorial and 77% with supratentorial tumors and occurs due to tension and compression of the dura mater. At the onset of the disease, headache is most often diffuse, dull, intermittent, bursting.

With an increase in intracranial pressure, the pain intensifies and becomes permanent. A characteristic, but not permanent feature of headaches arising as a result of the development of intracranial hypertension is their occurrence or intensification in the second half of the night, in the morning, which is associated with an increase in cerebrospinal fluid pressure during this period of the day. Sometimes, against the background of a constant headache, its paroxysmal intensification occurs, which is accompanied by vomiting, dizziness, and a decrease in the level of consciousness.

Typical for brain tumors should be considered the occurrence or increase of headache with excitement, physical exertion. The category of classics includes the relationship between the intensity of pain and the position of the patient's head in tumors of the fourth ventricle: pain decreases when the patient is positioned on the side of the tumor localization (Vruns' symptom), which is explained by the gravitational displacement of the tumor node. At the same time, in the elderly, even with a large tumor, pain symptoms may be absent for a long time. In benign neoplasms of the meninges, pain is local in nature, sometimes radiating to specific areas and, with a superficial location of the tumor node, may be accompanied by local pain on percussion. However, such variants of pain symptoms are less significant when making a preliminary diagnosis.

Vomiting occurs in 68% of patients with brain tumors. Most often, this symptom of a brain tumor is associated with the development of intracranial hypertension, but sometimes it can be caused by the presence of a tumor in the region of the fourth ventricle or cerebellum, which has a direct mechanical effect on the vomiting center. The classic characteristic of the so-called tumor vomiting is its occurrence in the morning, without preliminary nausea, on an empty stomach and at the height of the headache. After vomiting, the intensity of the headache decreases over time, which is associated with the onset of dehydrating affect and a decrease in intracranial pressure. The frequency of vomiting is variable.

A common neuro-ophthalmological symptom that reflects the presence of intracranial hypertension is congestion of the optic nerve discs. In most cases, this symptom is detected simultaneously on both sides, but sometimes its occurrence may vary in time. The rate of development of this symptom depends on the rate of increase of intracranial hypertension. Congestion of the optic nerve discs is most often determined in combination with other hypertensive symptoms. And only in certain cases (for example, in children) can the symptom be of a debut nature.

Increased intracranial pressure leads to disturbances in the activity of the peripheral parts of the visual analyzer, which is primarily associated with swelling of the optic nerve and retina. Subjectively, the patient notes the periodic appearance of a veil before the eyes, "flies" in the early hours. Long-term increase in intracranial pressure leads to the development of secondary atrophy of the optic nerves.

In this case, the decrease in visual acuity that occurs as a result of the development of atrophy is irreversible. Radical surgical intervention or long-term normalization of intracranial pressure often do not lead to a halt in the progression of vision loss. In the case of the development of a tumor process in the anterior or middle cranial fossa, compression of the optic nerve on the side of the tumor is often observed symptom F. Kennedy: a combination of primary atrophy of the optic nerve on the side of tumor growth with secondary atrophy of the opposite optic nerve due to the development of hypertensive syndrome.

Vertigo is observed as a general cerebral symptom in intracranial hypertension in 40-50% of patients with brain tumors. The occurrence of this symptom is associated with the development of congestion in the vestibular labyrinth and increased endolymph pressure in the semicircular canals. In some cases, it can manifest as an element of focal symptoms in tumors of the cerebellum, VIII nerve, pons and IV ventricle.

Patients describe the manifestation of the symptom as a feeling of rotation of surrounding objects and their own body, a feeling of falling. Dizziness caused by intracranial hypertension occurs at later stages of the development of the pathological process. In any case, this symptom usually occurs in attacks, often after a significant increase in intracranial pressure. Dizziness is often accompanied by nausea, vomiting, tinnitus, autonomic disorders, and even decreased clarity of consciousness.

Mental disorders in the context of the development of general cerebral symptoms of a brain tumor occur in 63-78% of patients. The main pathogenetic moments in the development of this type of disorders should be considered as a violation of blood perfusion of the brain tissue, especially its stem sections, which is a direct consequence of the increase in intracranial pressure, intoxication of the brain with decay products and factors that are produced in the tumor focus, as well as diffuse dysfunction and anatomical integrity of the associative pathways of the brain. It should also be noted that mental disorders are elements of focal symptoms in tumors of the frontal region. In this case, the development of mental disorders of the patient occurs under the influence of both general cerebral and local pathogenetic mechanisms.

The nature of mental disorders that occur with brain tumors may be different. Thus, against the background of clear consciousness, memory, thinking, perception, and concentration disorders may occur. In certain cases, aggressiveness, a tendency toward unmotivated behavior, manifestations of negativism, and decreased criticality come to the fore. Sometimes such symptoms of a brain tumor may shift to a phase of apathy and lethargy. In some cases, the development of a delirious state and hallucinations is observed.

In elderly patients, the development of mental disorders is almost always accompanied by an increase in intracranial pressure and is often the earliest clinical sign, especially in the presence of hypertension and atherosclerosis.

The level of consciousness is the main clinical equivalent of cerebral perfusion with blood and intracranial pressure. Therefore, the progression of intracranial hypertension inevitably leads to a gradual suppression of consciousness, which without adequate treatment, progresses to a state of stupor and coma.

The development of epileptic syndrome should also be included to a certain extent in the category of general cerebral symptoms of brain tumors and symptom complexes. According to various data, the occurrence of this syndrome is observed in 22-30.2% of patients with brain tumors, usually of supratentorial localization. Episyndrome most often accompanies the development of astrocytic tumors, less often - meningiomas. In 37% of patients, epileptic seizures are the debut symptom of a brain tumor.

Therefore, their occurrence without obvious causes at the age of over 20 years should be considered primarily from the point of view of oncological alertness. As in the case of mental disorders, not only general cerebral pathogenetic mechanisms play a role in the development of episyndrome, but also local (focal) effects of the tumor on brain tissue. This is especially important when analyzing the causes of the development of tumors of the temporal lobe and closely located areas of the brain.

In this case, the formation of an epileptic focus of increased excitability of nerve cells (for example, in the associative areas of the temporal lobe) occurs in the context of the development of focal symptoms "in the neighborhood". The local component in the formation of the epileptic syndrome also determines the nature of the aura preceding the seizure. For example, so-called motor auras are observed during the development of the epileptic syndrome in tumors of the frontal lobe, sensory hallucinations - in tumors of the parietal lobe, olfactory, auditory and complex visual - in tumors of the temporal lobe, simple visual - in tumors of the occipital lobe.

The nature of epileptic seizures that occur during the development of a brain tumor varies from minor seizures (petit mal) to generalized convulsive seizures (grand mal). An important sign that allows one to associate an epileptic seizure with the development of a tumor process is post-seizure loss of motor or speech function.

Focal symptoms arise as a result of local direct or indirect impact of the tumor on the brain tissue and reflect the disorder of certain parts of it (or individual cranial nerves). Primary (direct) focal symptoms are distinguished, which reflect the result of the tumor's effect on the immediately adjacent parts of the brain, as well as secondary focal symptoms, in the development of which the main role is played not so much by the direct mechanical impact of the tumor, as by ischemia and edema-swelling of the surrounding brain tissue. Depending on the degree of remoteness of the focus of secondary symptoms from the tumor node, it is customary to distinguish between the so-called symptoms "nearby" and "at a distance".

The mechanisms of development of focal symptoms are different. Thus, primary focal symptoms of a brain tumor arise due to direct mechanical and chemical impact of the tumor focus on the adjacent brain tissue and its ischemia. The degree of expression and duration of such impact determine the nature of the primary focal symptoms: initially, symptoms of irritation or hyperfunction of the specified area of brain tissue appear, which are subsequently replaced by symptoms of loss.

Symptoms of irritation include Jacksonian and Kozhevnikovian epileptic seizures, formed and unformed hallucinations, epileptic equivalents, auras. Symptoms of loss include paresis, paralysis, visual defects, aphasia, anesthesia.

The occurrence of symptoms “in the neighborhood” is associated with ischemia of the corresponding areas of the brain due to primary compression, as well as due to the mechanical impact of the tumor on the main vessels that supply blood to the corresponding areas of the brain (for example, brainstem symptoms in cerebellar tumors, motor aphasia in tumors of the pole of the left frontal lobe, damage to the nerves of the III and IV pairs in tumors of the temporal lobe).

Symptoms of a brain tumor "at a distance" arise only in the case of a far-reaching process and, with the progression of general cerebral symptoms, can develop into dislocation syndromes. Examples of symptoms "at a distance" are verbal hallucinosis in tumors of the posterior cranial fossa, symptom complexes that arise with compression of certain areas of the brain during dislocation.

When brain tissue is dislocated, it may become trapped in anatomical apertures inside the skull or at its exit. This situation is referred to as "wedge" of a particular area of the brain.

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Diagnostics brain tumors

Preoperative diagnosis of a brain tumor includes the following components: nosological, topical and pathohistological diagnosis. If a patient is suspected of having a brain tumor, the first priority is to conduct a general and neurological examination with a topical diagnosis. Concomitant examinations should include examinations by a neuro-ophthalmologist and an otoneurologist, and if a metastatic nature of the oncological process is suspected, other specialists.

An ophthalmologist consultation is a mandatory condition of the diagnostic process and should include an assessment of visual acuity, determination of visual fields, and examination of the fundus. The latter allows one to identify indirect signs of increased intracranial pressure in the form of congested optic discs, their secondary atrophy, and also to determine the presence of primary optic nerve atrophy, which may indicate the localization of the tumor node.

To establish a clinical diagnosis, it is necessary to use additional instrumental research methods, among which the most informative at present are MRI and CT.

These methods, with their modern availability, allow visualization of the tumor focus, assessment of its size and anatomical and topographic features, which constitutes the bulk of the information necessary for choosing the tactics of surgical treatment. In cases where the information obtained using CT or MRI is insufficient to choose the tactics of treatment, predict its results, and also to improve the quality of surgical intervention, angiography methods are used (currently considered mandatory in the context of preoperative preparation).

In order to quickly assess the degree of displacement of the midline structures, the echoencephalography method can be used. Methods such as positron emission tomography (PET), single photon emission computed tomography (SPECT), electroencephalography (EEG), and Dopplerography are used to clarify the diagnosis.

X-ray examination methods (primarily craniography) in the diagnosis of brain tumors have currently lost their key importance. Classical X-ray signs of the presence of hypertensive syndrome and brain tumor are osteoporosis of the dorsum and tubercle of the sella turcica, posterior clinoid process, as well as visualization of a pronounced pattern of finger impressions on the inner surface of the bones of the cranial vault, diffuse enhancement of the channels of the diploic veins, expansion and deepening of the pits of the pacchion granulations. In early childhood, the presence of intracranial hypertension leads to divergence of the sutures of the skull, a decrease in the thickness of the bones, and an increase in the size of its brain part.

In addition to the radiological symptoms of hypertensive osteoporosis of bone tissue, in rare cases osteolysis or hyperostosis may be observed in the growth areas of certain types of tumors. Sometimes calcification of tumor areas or displacement of the calcified pineal gland is observed.

SPECT and radioisotope scintigraphy methods allow us to determine the primary lesion when there is a suspicion of a metastatic nature of a brain tumor, to evaluate some features of the tumor biology and, on this basis, to clarify the assumption about its possible histological type.

Currently, the method of stereotactic puncture biopsy of the tumor focus is widely used, which allows for an accurate histological diagnosis.

In addition to instrumental methods, it is also possible to use a number of laboratory studies, such as determining the hormonal profile (if pituitary adenoma is suspected), and virological research.

A full liquor study (determination of cerebrospinal fluid pressure, its cytological and biochemical composition) is currently not. Determining and diagnosing a brain tumor, and often performing a lumbar puncture is dangerous due to the risk of developing a herniation. Changes in the pressure and composition of the cerebrospinal fluid inevitably accompany the development of the tumor process. The pressure of the cerebrospinal fluid and, consequently, intracranial pressure can increase by 1.5-2 times compared to normal values.

As a rule, the degree of intracranial pressure change is somewhat lower than the given range of extreme upper values. The so-called symptom of protein-cell dissociation is considered classic, which reflects a significant increase in the concentration of protein in the cerebrospinal fluid with a normal or slightly increased cell count. Such a picture is observed only in the case of an intraventricular or close to the ventricular system location of the tumor node. A significant increase in cells in the cerebrospinal fluid is observed in malignant neoplasms of the brain with phenomena of disintegration of tumor nodes (glioblastoma). In this case, centrifugation of the cerebrospinal fluid allows you to obtain a cellular residue, in which tumor cells can be detected in 25% of patients. In rare cases, with the development of hemorrhage in the tumor focus, with extensive disintegration of the tumor node and intensive development of the vascular network of the intraventricular tumor, the cerebrospinal fluid can become xanthochromic.

In the case of clinical signs indicating an increase in intracranial pressure, dislocation of parts of the brain, as well as in the determination of congestion in the fundus, lumbar puncture is strictly contraindicated due to the risk of wedging of the cerebellar tonsils into the cervicodural funnel, which inevitably leads to the death of the patient.

The diagnostic features of metastatic tumors include the use of CT and MRI in contrast mode, stereotactic tumor biopsy, radiography (or CT) of the chest organs, skeletal system, CT of the abdominal organs and pelvic cavity, scintigraphy (spine, pelvis and limbs), and mammography in women.

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Treatment brain tumors

The treatment of brain tumors is based on complexity. Currently, in most cases, surgical, chemotherapeutic and radiotherapeutic methods are used in the treatment of brain tumors.

Surgical methods of treating brain tumors should currently be considered as the complete or partial removal of tumor cell mass (actually surgical interventions) or the initiation of acute radiation necrosis of tumor cells (radiosurgical interventions).

Chemo- and radiotherapeutic methods of influencing the tumor focus lead to the prolonged death of a certain number of tumor cells, which is of greatest importance for reducing the population of oncogenic progenitors in the normal brain tissue - on the periphery or at a distance from the tumor focus.

Surgical treatment of brain tumors includes radical operations aimed at the most complete removal of the tumor, as well as palliative interventions carried out to reduce intracranial pressure and prolong the life of the patient.

Depending on the degree of completeness, surgical removal of the tumor can be total, subtotal, and partial.

Currently, performing surgical interventions for the removal of brain tumors requires the use of the latest technological developments and modern equipment, which includes optical magnification systems (surgical microscopes), intraoperative neuroimaging systems (intraoperative MRI and CT units), intraoperative X-ray monitoring systems, stereotactic units. In combination, intraoperative visualization methods allow navigation monitoring of the surgeon's actions in relation to brain structures.

Thermal destruction (laser thermal destruction, cryodestruction) and ultrasonic destruction-aspiration are often used to remove the tumor focus.

Radiosurgical destruction of brain tumors is based on single targeted irradiation of the tumor node through intact skin using radiosurgical installations - y-Knife, linear accelerator (Linac), Cyber-Knife, etc. The total radiation dose to the tumor node is 15-20 Gy. The spatial error in focusing the y-rays for the y-Knife installation does not exceed 1.5 mm. In this case, the size of the brain tumor should not exceed 3 - 3.5 cm in maximum diameter. Radiosurgical treatment is mainly used for metastatic foci in the brain, meningiomas and neurinomas.

Palliative treatment of brain tumors (aimed at reducing the severity of hypertensive and dislocation syndromes):

1. surgical methods for reducing intracranial pressure (among the most effective: external decompression by craniotomy, internal decompression by removing a significant portion of the tumor lesion or resection of brain tissue);
2. restoration of normal intracranial pressure and release of areas of brain tissue compressed during dislocation (tentoriotomy for temporotentorial herniation);
3. restoration of normal cerebrospinal fluid flow (cerebrospinal fluid shunting operations: ventriculostomy, ventriculocisternostomy, ventriculoperitocyostomy, ventriculocardiostomy).

Taking into account the main pathophysiological moments of the development of edema-swelling of brain tissue in brain tumors, the pathogenetic treatment of these syndromes implies;

1. normalization of external respiration;
2. optimization of systemic arterial pressure levels;
3. facilitating venous outflow from the cranial cavity (the upper half of the body is raised at an angle of 15) and other conservative methods of direct or indirect reduction of intracranial pressure (moderate hyperventilation, craniocerebral hypothermia, administration of osmotic diuretics).

Radiation therapy is used for subtotal removal of some types of brain tumors or in the complex treatment of malignant tumors. There are different types of this treatment: traditional, hyperfractionated, photodynamic therapy, brachytherapy, boron neutron capture therapy.

The total radiation dose during the course of radiotherapy is up to 60 Gy. The course of radiotherapy is prescribed 2 days after tumor removal and lasts for 6 weeks with daily fractional irradiation sessions with a dose of 180-200 mGy. The most radiosensitive brain tumors are: malignant glioma, oligodendroglioma (with subtotal resection or anaplastic variant), dysgerminoma, primary CNS lymphoma, medulloblastoma, ependymoma, meningioma (malignant variants, subtotal or partial removal), pituitary adenoma (after subtotal removal or in case of ineffectiveness of drug therapy), chordoma of the base of the skull.

Depending on the method of drug administration, chemotherapy can be systemic, regional, intra-arterial (selective), intrathecal and interstitial. A mandatory condition for a course of chemotherapy is preliminary testing of the tumor for sensitivity to the drugs used. The most chemosensitive are brain tumors such as malignant gliomas, primary CNS lymphomas, and tumor infiltrations of the meninges.

Hormonal therapy (to reduce cerebral edema, as well as hormone replacement therapy), immunotherapy (specific, non-specific, combined, administration of monoclonal antibodies, use of antitumor vaccines, etc.), and gene therapy are currently being considered as promising methods of treating brain tumors.

Treatment of metastatic brain tumors has its own characteristics: if there is one metastatic lesion located laterally, it is surgically removed and a course of radiation therapy is prescribed. If a single lesion is located medially, radiosurgical treatment and a course of radiation therapy are indicated.

If there are several foci, among which one large foci stands out, which gives clear clinical symptoms and is located laterally, it is removed and a course of radiation therapy is prescribed. If there are three or more foci, the use of radiosurgical treatment and a course of radiation therapy for the entire head area is indicated. If the foci are located laterally, their surgical removal is possible. If there are a large number of foci, a course of radiation therapy is indicated.