What is an astrocytoma and how can it be treated?

The central nervous system is made up of a wide network of cells specialized in the conduction and processing of information. Gliomas are tumor conditions of the nervous tissue and astrocytoma is its most common form of presentation. Are you interested in knowing what it is and how it can be treated?

Astrocytoma is a type of primary brain tumor that develops from a group of nerve cells called astrocytes. These are responsible for providing support to neurons, however, they can grow uncontrollably and form this type of neoplastic condition.

The tumor process originates from any part of the nerve axis. It is common in the brain and spinal cord. The speed of development is variable; some are slow growing, while others do it aggressively. Symptoms and therapy will depend on the location and severity.

Grades and types of astrocytomas

Astrocytoma is classified based on its histological and tumor characteristics during microscopic study. Morphology, growth rate, and associated vascular proliferation must be considered. They range from grade 1 to grade 4.

Most of these neoplasms affect people over 40 years of age and its severity increases as the age of the patient increases. However, according to the American Association of Neurological Surgeons (AANS), grade 1 astrocytomas are more common in pediatric patients.

Grade 1

It is a slow-growing, circumscribed neoplastic mass that does not invade the brain tissue around it. Therefore, they usually have a very good prognosis and require only surgical recession.

Pilocytic astrocytoma at the level of the cerebellum is its most common form of presentation. Similarly, pleomorphic xanthoastrocytoma and subependymal giant cell astrocytoma (SEGA) are also included.

Read also: Physiology of the cerebellum

Grade 2

Is a Diffuse astrocytoma that invades and infiltrates the surrounding nervous tissue. There is usually no clear differentiation between healthy tissue and tumor cells.

Cells of abnormal morphology and growth are evident under the microscope. Surgical treatments, in most cases, are accompanied by radiation therapy and chemotherapy.

3rd grade

This is a Anaplastic astrocytoma that is characterized by being more aggressive and malignant than the previous ones. It has an accelerated growth rate and great infiltration in the nervous tissue.

In these cases, the surgical resolution is not definitive and requires several sessions of radiotherapy and chemotherapy.

Grade 4

The gioblastoma is the form of presentation with higher rate of malignancy and tissue invasion. Under the microscope, a large number of cells with morphological alterations and a high duplication rate, areas of dead tissue and new blood vessels are usually observed.

Unfortunately, it is responsible for more than 50% of the cases. In young patients it usually evolves from a minor stage brain tumor, while in those over 60 years it is initially diagnosed as a grade 4 tumor.

Symptoms of astrocytoma

The clinical manifestations of astrocytoma depend on its location in the brain and its tumor characteristics. High-grade ones tend to show symptoms early, due to infiltration and damage to nerve tissue.

For its part, low-grade astrocytomas may have symptoms late, once the tumor mass has reached a considerable size. Among the symptoms associated with patients with astrocytoma, the following stands out:

• Prolonged headache
• Cloudy or double vision.
• Difficulty speaking
• Loss of memory.
• Inability to concentrate
• Decrease or loss of muscle strength.
• Seizures
• Frequent vomiting

What can cause an astrocytoma?

Nowadays, there is no specific agent or cause to attribute the development of an astrocytoma at the level of brain tissue. However, it has been determined that there are several intrinsic and extrinsic factors related to a higher prevalence of the disease.

Risk factor's

Astrocytoma, like other neoplastic processes in the body, is associated with genetic, hereditary and environmental factors that determine the appearance and prognosis of the disease, among which the following stand out:

• Family background: evidence of a direct blood relative with an astrocyte tumor doubles the probability of developing this type of condition. In fact, it has been shown that there is an important genetic factor in the genesis of glioblastomas by mutation.
• Ionizing radiation: Ionizing radiation emitted by radiotherapy equipment or by contaminated environments increases the risk of suffering from tumor diseases. Also, some imaging devices, such as CT scans and X-rays, also use them.

• Age: the incidence and severity of glial tumors increases as a person ages. However, pilocytic astrocytomas are more common in young people.

Diagnostic tests for astrocytoma

Given the evidence of any strange symptoms, it is vital to go to a specialist doctor early. He will make the correct assessment of the neurological status and will request a series of tests that will allow to confirm the diagnosis.

Neurological evaluation

The neurological examination of the patient is based on different maneuvers and tests that assess the state of the nervous system. It includes the study of muscle strength and tone, reflex response, coordination, balance and sensitivity, as well as the state of the cranial nerves.

Imaging tests

The imaging study is vital for the identification of tumor pathologies at the level of brain tissue. Usually, Magnetic resonance imaging (MRI) is the most widely used in the diagnosis of astrocytoma.

It is usually performed accompanied by contrast media that facilitate the location of the tumor and the establishment of a therapeutic plan.

Similarly, the following studies can be used:

• Spectroscopy.
• Computed tomography (CT).
• Positron emission tomography (PET).

You may be interested in: Differences between CT and MRI

Biopsy

Needle biopsy is a crucial part of the definitive diagnosis of a brain tumor. The same it can be performed in a guided way by magnetic resonance imaging or by computed tomography. The sample obtained must be sent to the pathologist specialist.

Microscopic studies allow the staging or grading of the astrocytoma in order to establish a prognosis and define the therapeutic behavior with the patient.

Astrocytoma Treatments

In most astrocytomas, the first step in the treatment protocol includes surgical resolution by removal of the tumor mass. It allows to reduce the effect and the pressure at the intracranial level, thus reducing the symptoms.

Similarly, in more serious tumor processes, treatment with radiotherapy and chemotherapy is indicated. Radiation therapy has shown great effectiveness during the first months, especially after the surgical recession. The protocol includes small doses, 5 days a week for 6 weeks.

Chemotherapy with temozolomide (TMZ) is the most used in the management of grade 3, 4 astrocytomas and some grade 2 tumors. Administered orally in 5-day cycles with intervals of 3 weeks of rest. Side effects of radiation therapy and chemotherapy include anemia, fatigue, weakness, and hair loss.

Astrocytoma prognosis

The evolution of an astrocytic tumor process depends on several factors specific to the neoplastic lesion, the therapeutic approach used and the affected patient. Usually, its appearance in young patients determines a better course than in elderly patients.

On the other hand, the minimal clinical condition with a higher degree of functional response is associated with a better prognosis of the pathology. Regarding the therapeutic protocol, the greater the recession of the tumor, the greater the associated survival.

Similarly, the early implementation of adjuvant therapies, such as radiotherapy and chemotherapy, are associated with an increase in the survival rate. Furthermore, a crucial factor in the projection of life of a patient with astrocytoma is the severity and the form of presentation.

The survival rate associated with grade 1 astrocytic tumors is greater than 8 years. Usually by surgical removal. On the other hand, grade 2 and 3 tumors show a survival of 5 to 3 years, while for grade 4 the projection is 15 months.

Timely medical care for these tumors

Astrocytoma is a brain tumor that shows highly variable growth characteristicsAlthough most people usually experience symptoms early. They usually manifest as headaches that last throughout the day, blurred vision, and frequent vomiting.

In these situations, it is advisable to seek medical help immediately. Attendance, assessment, and early approach offer a better course. Early diagnosis makes it possible to consider the different therapeutic options and adapt them to the patient's needs.