It is the most common type of “primary” brain tumor within the group of brain tumors called gliomas.
Primary means that they have originated in the brain instead of spreading from other places.
They grow from a type of cell called an astrocyte, which is the most abundant cell in the brain. They support and protect neurons and help pass messages between them. Astrocytes, therefore, are vital to processing information in the brain.
What causes Astrocytoma?
As with most brain tumors, the cause is not known. The scientific investigations and medicinal studies have not detected the possible reasons that generate these types of tumors; the conclusions always focus on our genes.
Genes control the way cells grow and divide. Mutations can cause this process to go wrong, which causes the cells to grow out of control and form tumors.
These changes are often the result of a mistake made by the cell when it copies the DNA before dividing.
Therefore there is nothing you could or can do to avoid suffering from a primary brain tumor or an Astrocytoma.
Brain tumors graduate from 1 to 4, according to their appearance and how they behave. To determine the type of tumor, we study how fast they grow and the probabilities of spreading:
First-degree astrocytomas (pilocytic) are slow-growing, relatively contained, and unlikely to spread to other parts of the brain.
When removed surgically, it is unlikely that they will grow back. They develop in the cerebellum, where the balance is controlled. They can also occur in the optical pathways involved in view.
Second-degree Astrocytoma (diffuse): diffuse because it does not have well-defined edges, making it more challenging to eliminate. They grow slowly, but sometimes they can come back after treatment.
Third-degree Astrocytoma (anaplastic): they increase and are often called malignant or cancerous. Sometimes they reappear after treatment in a more advanced form, fourth-degree Astrocytoma.
Fourth-degree Astrocytoma (glioblastoma) is so invasive that it is usually fatal.
How are Astrocytomas treated?
The treatment for astrocytomas depends on the grade of the tumor, as well as its size and location:
First and second degree: Treatment in adults is usually surgery to remove as much of the tumor as possible; the amount depends on the location and size. This is called “total or complete resection if it is eliminated.”
There may be no need for further treatment, but your treating doctor will continuously monitor it to ensure it does not grow again.
This is called ‘watch and wait,’ where no treatment is given unless your tumor changes or grows or symptoms worsen.
If the tumor can not be removed entirely, the surgeon will remove it as much as possible. This is known as cytoreduction or partial resection, the procedure most frequently used for cases of second-degree astrocytomas, whose edges are less defined.
Radiation therapy may also be given to remove any tumor cells that could not be reached during surgery. Again, this is more likely in cases with second-degree tumors.
Occasionally, chemotherapy may also be given. For children, chemotherapy is often the first line of treatment instead of surgery. Doctors try to avoid giving radiation therapy to children under three years of age.
Third degree: As these tumors grow faster and are more likely to spread, the usual course of treatment is surgery followed by radiation therapy and, sometimes, chemotherapy.
Radiation therapy can last for several weeks and is rarely used in children under three years.
For chemotherapy, the drug Temozolomide is used frequently.
Alternatively, another chemotherapy drug, Carmustine, can be placed directly in the brain during surgery in adults. Carmustine will be released gradually as it dissolves for 2 to 3 weeks.
What is the prognosis?
Information about the prognosis can be challenging; some people do not want to know, while others do. There is no wrong or correct answer about whether or not to receive that information.