Astrocytoma: types, symptoms, causes and treatment

This type of cancerous formation is considered a serious pathology of the nervous system.

"You have a tumor." This is probably one of the phrases we are most afraid of hearing when we go to the doctor for a check-up or undergo tests for a problem for which we do not know the cause. And the fact is that Cancer is one of the most common cancer is one of the most feared diseases worldwide, being one of the worldwide, being one of the best known and leading causes of death worldwide and one of the main challenges of medicine, along with AIDS and dementia.

Among the many locations in which it can appear, the brain is one of the most dangerous, since even a benign, non-cancerous tumor can cause serious effects and even death. Among the different types of brain tumors that exist, one of the most common are astrocytic brain tumors, one of the most common are the astrocytomaswhich we are going to talk about in this article.

What are astrocytomas?

We call astrocytoma any neoplasm or tumor formed mainly by astrocytes, one of the main types of glial cells that nourish and supportone of the main types of glial cells that feed and support neurons. This tumor is therefore a mass of astrocytes that is produced by an abnormal, pathological and uncontrolled growth and proliferation of one of the types of glial tissue present in the nervous system, being one of the main types of brain tumor.

Astrocytomas are tumors whose symptoms can vary greatly depending on the location or locations in which they appear, whether they compress other brain areas, their proliferative capacity or whether they infiltrate other tissues or are self-limiting. However, at a general level it is common to find the existence of headaches, nausea and vomiting, drowsiness and fatigue, altered consciousness and confusion. Personality and behavioral disturbances are also relatively common. Fever and dizziness are also common, as well as unreasonable weight changes, perception and language problems and loss of sensation and mobility, and even seizures. It is also possible, especially when they occur in children, that malformations may be generated and alteration of the craniofacial anatomy, both intracranially and extracranially..

This type of tumor can occur, as with other tumors, in a circumscribed manner to a specific region or structure or in a diffuse manner, with the former having a much better prognosis than the latter. They do not usually metastasize to other areas of the body beyond the nervous system, although they do spread within the nervous system.

Diagnosis

The diagnosis of these tumors is complex and several procedures are necessary. First of all it is necessary to perform a biopsy of the tumor, which will allow us to take a sample of the tumor.This will allow us to take a sample of the brain tumor, currently performed by stereotaxy. Subsequently it will be necessary to perform a phenotypic and histological analysis to check the type of tissue we are talking about, as well as its behavior. Finally, it will be necessary to evaluate the proliferative capacity, in order to be able to determine its degree and infiltration capacity.

Causes

As with all other brain tumors, the causes of astrocytomas are mostly unknown. However, some hereditary disorders may facilitate their occurrence, such as neurofibromatosis. Infection with the Epstein-Barr virus or previous radiotherapy due to another tumor also appear to be risk factors for developing astrocytomas.

Classification according to grade

The term astrocytoma, as we have already indicated above, groups together all tumors or neuplasias consisting mainly of astrocytes. But within the astrocytomas we can find various classifications and divisions, depending ondepending, among other criteria, on their degree of malignancy and proliferation. In this sense, we can observe the existence of four grades of severity

Grade I

All those tumors whose main characteristic is their benignity are considered as grade one astrocytomas. Because of this, they can cause serious problems and can even be fatal or cause disability depending on whether they grow and cause parts of the brain to be crushed against the skull. They are rare tumors, predominantly in children, which have the advantage of having a very high survival rate. advantage of having a very high survival rate and being relatively easy to treat. and are relatively easy to treat. In many cases surgical resection is sufficient. An example of tumors of this grade is pilocytic astrocytoma.

Grade II

In contrast to grade I astrocytomas, grade II astrocytomas are actually cancer, being malignant tumors. Grade II astrocytomas are aggressive, much more complex to treat and are considered malignant and expansive. They usually generate epileptic seizuresand diffuse lesions are observed. Generally this group includes diffuse astrocytomas, among which the most common are fibrillary, gemistocytic and protoplasmic astrocytomas. They are the most common type of low-grade astrocytoma.

Grade III

Grade three astrocytomas are a type of malignant tumor that is a type of malignant tumor that has a high capacity for proliferation and infiltration into other structures. infiltration into other structures. The best known is the anaplastic astrocytoma. It is frequent that it is the evolution of one of the previous tumors and even evolves into a grade four tumor.

Grade IV

Astrocytomas that are more invasive, aggressive and infiltrative, rapidly spreading to other areas of the brain, are considered grade four. The most typical and well-known astrocytoma with this degree of malignancy is glioblastoma multiforme, being in fact the most frequent type of brain neoplasm. The prognosis is usually fatal and life expectancy is greatly reduced.

The two most frequent

The following are some of the most frequent characteristics of some of the two most common and well-known types of astrocytoma.

Glioblastoma multiforme

The most common of all astrocytomas and one of the most frequent brain tumors (about a quarter of all diagnosed brain tumors are glioblastomas), it is also the most aggressive and has the worst prognosis. It is a tumor in which the cells are poorly differentiated, which reproduces at high speed and proliferates at the vascular level, leading to death and degeneration. generating death and degeneration of other structures by necrosis.. Life expectancy does not usually exceed one year and three months. It can be primary, appearing by itself, but it is generally an evolution of one of the tumors of lesser degree of malignancy.

Anaplastic astrocytoma

The second of the best known and most malignant types, this is a grade III astrocytoma that tends to infiltrate the surrounding tissue without destroying it, resulting in a thickening of the surrounding tissue. It usually generates edema around the affected area, although it does not usually generate necrosis. Survival is longer than in glioblastoma, although only about 20% survive more than five years. It has been debated whether there is a hereditary genetic predisposition in some subjects because some do not. in some subjects because some hereditary syndromes predispose to its appearance.

Treatments

The treatment of a brain tumor such as astrocytomas is something that must be carefully planned, taking into account that we are dealing with an intervention that can generate alterations in the brain. an intervention that can generate alterations in different brain regions beyond the one directly affected by the astrocytoma. beyond the one directly affected by the tumor. However, even if secondary alterations occur, the priority must be the integrity of the brain.

Surgery to resect the tumor is one of the main treatment modalities for astrocytomas, being the initial treatment to be applied in practically all cases and after which other therapies will be applied to eliminate the remains of the tumor or prevent its expansion. However, sometimes resection will not be possible, sometimes complete resection will not be possibleHowever, sometimes complete resection will not be possible, as in cases where the tumor is located in the brain stem (since its resection could result in the death of the subject as this area controls vital functions).

This resection is carried out in both low grade and high grade tumors, although in the latter it is common for recurrence and infiltration of other brain areas to occur. This is due to the fact that even in these cases resection can improve the patient's mental capacities which were diminished by the pressure of the tumor. Once as much of the tumor as possible has been removed, radiotherapy and chemotherapy are usually used to combat the radiotherapy and chemotherapy are usually used to combat the remains of cancerous cells..

In the case of radiotherapy, we are dealing with the application of high doses of radiation to cancerous tissues in order to destroy the cells and reduce or eliminate tumors, and it has been found to be very effective in tumors with a high degree of malignancy. It is necessary to take into account the need to focus the radiation only on the cancerous area, since if it is used in a generalized manner, an excessive amount of healthy cells would be destroyed.

Chemotherapy is the application of potent chemicals and drugs used to combat the tumor, generally by inhibiting tumor proliferation by applying substances that prevent cell division and DNA repair.. These substances include temozolomide, ifosfamide, etoposide, carboplatin or lomustine.

At the psychological level, intervention is also advisable, especially when there are symptoms and alterations of anxiety and mood. Psychoeducation is fundamental, especially in those cases in which the only possible treatment is only palliative and/or are in the terminal phase. It is also essential to have a safe and reliable space in which to solve doubts and express feelings and fears without fear of being judged, something frequent in this type of disease. Likewise, there are therapies such as adjuvant psychological therapy, creative innovation therapy or visualization therapy that can be applied in order to help the subject to have greater perception of control over their disease.

Bibliographic references:

• Buckner, J.C.; Brown, P.D.; O’Neill, B.P.; Meyer, F.B.; Wetmore, C.J. & Uhm, J.H. (2007). Central Nervous System Tumors. Mayo Clinic Proceedings, 82: 1271-86.
• Kleihues, P.; Burger, P.C. & Scheithauer, B.W. (1993). The new WHO classification of brain tumours. Brain Pathol 3 (3): 255-68.
• Michaud, D.S. (2016). Epidemiology of brain tumors. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SK, eds. Bradley's Neurology in Clinical Practice. 7th ed. Philadelphia, PA: Elsevier.
• Pérez, L.; Galarraga, J.; Gómez, H. & Tamayo, J.D. (2000). Clasificación de los gliomas astrocíticos. Breves consideraciones. Rev. Neurol., 31:1180-1183.