“You have a tumor.” This is probably one of the phrases we are most afraid of hearing when we go to the doctor for an exam or get tested for a problem we don’t know the cause of. And this is it cancer is one of the most dreaded diseases in the world, being one of the best known and most important causes of death in the world and one of the major challenges of medicine alongside AIDS and dementia.
Among the many places where it can appear, the brain is one of the most dangerous, as even a benign non-cancerous tumor can cause serious effects and even death. In the different types of brain tumors that exist, one of the most common is astrocytomas, Which we will talk about in this article.
What are astrocytomas?
We call astrocytoma a any neoplasm or tumor formed mainly by astrocytesOne of the main types of glial cells that feed and support neurons. This tumor is therefore a mass of astrocytes that occurs in the face of 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 widely depending on where or where they appear, whether they compress other areas of the brain, their proliferative capacity, or if they infiltrate other tissues. or self-limit. However, in general, it is common to find the existence of headache, nausea and vomiting, drowsiness and fatigue, altered consciousness and confusion. It is also relatively common for personality and behavioral disorders to occur. Fever and dizziness are also common, as are weight disturbances for no reason, problems with perception and language, loss of feeling and mobility, and even seizures. It is also possible, especially when they occur in children, that malformations are generated and that the intracranial and extracranial craniofacial anatomy be modified.
This type of tumor can occur, as with other tumors, circumscribed to a specific region or structure or in a diffuse manner, the former having a much better prognosis than the latter. They usually do not metastasize to other areas of the body beyond the nervous system, although they do grow there.
The diagnosis of these tumors is complex and several procedures must be performed. A tumor biopsy should first be taken, This will allow us to take a sample of the brain tumor, currently performed by stereotaxis. Subsequently, it will be necessary to perform a phenotypic and histological analysis to verify 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 finish determining its degree and its infiltration capacity.
As with other brain tumors, the causes of astrocytomas are mostly unknown. However, some inherited disorders can make it easier for them to appear, such as neurofibromatosis. Epstein-Barr virus infection or previous radiation therapy due to another tumor also appear to be risk factors for their development.
Classification according to diplomas
The term astrocytoma, as we indicated above, includes all tumors or neoplasms made up mainly of astrocytes. But in astrocytomas we can find various classifications and divisions, Based among other criteria on its degree of malignancy and proliferation. In this sense, we can observe the existence of four degrees of gravity
All of these tumors are considered grade 1 astrocytomas, the main characteristic of which is their benignity. Weight at this can cause serious problems and even be fatal or disability as they develop and cause parts of the brain to crash against the skull. These are rare tumors, mainly infantile, which they have the advantage of having a very high degree of survival and are relatively easy to treat. In many cases, surgical resection is sufficient. An example of tumors of this grade is found in pilocytic astrocytoma.
Unlike grade I astrocytomas and grade II astrocytomas themselves are actually cancers, malignant tumors. Aggressive grade two astrocytomas, much more complex to treat and considered to be malignant and expansive. They usually cause epileptic seizures, Observation of diffuse lesions. Generally in this group are included the diffuse astrocytomas, among which the most usual we can find the fibrillar, gemistocítico and protoplasmático astrocytomas. They are the most common type of low grade astrocytoma.
Grade 3 astrocytoma result a type of malignant tumor that has a great capacity for proliferation and infiltration to other structures. The best known is anaplastic astrocytoma. It is common for it to grow from any of the above tumors and even grow to a grade 4 tumor.
Fourth-grade astrocytomas are considered to be more invasive, aggressive and infiltrating, rapidly spreading to other areas of the brain. The most typical and well-known astrocytoma with this degree of malignancy is glioblastoma multiforme, being in fact the most common type of brain neoplasm. The prognosis is usually fatal and the life expectancy is considerably reduced.
The two most common
Here are some of the more common characteristics of some of the two most common and well-known types of astrocytoma.
The most common of all astrocytomas and one of the most common brain tumors (about a quarter of brain tumors diagnosed are glioblastomas) is also the most aggressive and the worst prognosis. It is a tumor whose cells are poorly differentiated, which reproduces at high speed and proliferates at the vascular level. causing death and degeneration of other structures by necrosis. Usually, life expectancy does not exceed one year and three months. It can be primary, appearing on its own, but it is usually an evolution of some of the tumors of the lowest degree of malignancy.
The second of the most famous and malignant types, it is a grade III astrocytoma that tends to infiltrate the surrounding tissues without destroying them completely, appearing a thickening of these. It usually causes edema around the affected area, although it usually does not cause necrosis. Survival is higher than in glioblastoma, although only about 20% survive more than five years. It has been discussed whether there is a hereditary genetic predisposition in certain subjects because certain hereditary syndromes predispose to its appearance.
Treating a brain tumor like astrocytomas is something that needs to be carefully planned, as it involves a procedure that can cause changes in different areas of the brain beyond that directly affected by the tumor. However, even if secondary changes do occur, the priority should be integrity.
Surgery to perform tumor resection is one of the main modalities of treatment for astrocytomas, being the initial treatment to be applied in almost everything and after which other therapies will be applied to remove the remains of the tumor or prevent its expansion. . however, sometimes a complete resection will not be possibleAs in cases where the tumor is located in the brainstem (since its resection could lead to the death of the subject by controlling this area of vital functions).
This resection is performed at in both low-grade and high-grade tumors, although in the latter it is common for recurrences and infiltrations to occur in other areas of the brain. This is due to the fact that even in these cases the resection can improve the mental capacities of the patient which have been diminished by the pressure of the tumor. Once the maximum possible amount of tumor has been removed, they are usually used radiation therapy and chemotherapy to fight cancer cell remnants.
In the case of radiotherapy, we are faced with the application of large doses of radiation to cancerous tissues in order to destroy cells and shrink or eliminate tumors, y.se has been shown to be very effective in tumors of high degree of malignancy. It is necessary to take into account the need to concentrate the radiation only on the cancerous area, because if it were used in general, a large number of healthy cells would be excessively destroyed.
Chemotherapy is the application of strong chemicals and drugs used to fight the tumor, usually by inhibiting tumor proliferation when applied. substances that prevent cell division and DNA repair. These substances include temozolomide, ifosfamide, etoposide, carboplatin or lomustine.
Psychologically, intervention is also recommended, especially in the event of symptoms and alterations in anxiety and mood. Psychoeducation is essential, especially in cases where the only possible treatment is only palliative and / or terminally ill. It is also essential to have a safe and reliable space to resolve doubts and express feelings and fears without fear of being judged, which is common in this type of illness. There are also therapies such as adjuvant psychotherapy, creative innovation therapy, or visualization therapy that can be applied to help the subject gain a better sense of control over their disease.
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