What is an astrocytoma?

Astrocytomas are tumors found in the central nervous system (CNS) that grow from star-shaped astrocyte cells. Astrocytes are glial cells (the type of cells that provide supportive tissue in the brain).

Some types of astrocytomas have small areas of infiltration, while others are more spread out. There are several types of astrocytomas, including:

  • Pilocytic: These tend to not spread and are considered to be noncancerous.
  • Diffuse: These grow slowly.
  • Anaplastic: These are rare but call for aggressive treatment.
  • Glioblastoma: This type grows aggressively and is the most common cancerous primary brain tumor.
  • Subependymal giant cell astrocytoma: This type is linked with tuberous sclerosis, a genetic condition.

Where are astrocytomas found most often?

Most of these tumors are found on the outer curve of the brain. Often, they are found at the top of the brain. Sometimes, they can develop at the base of the brain. Astrocytomas found in the brainstem or spinal cord occur less frequently.

Who is at risk for developing astrocytomas?

The average annual age-adjusted incidence rate for tumors of neuroepithelial tissue (which includes astrocytomas) is 6.6 per 100,000, according to figures from the Central Brain Tumor Registry of the United States in 2016.

Most cases of pilocytic astrocytomas are diagnosed by the age of 20. About 1,200 people younger than 19 in the United States will have an astrocytoma diagnosis. The 20-45 year age group accounts for about 60% of all low-grade astrocytoma diagnoses. A genetic component has been found in some cases. Males are only slightly more likely to develop astrocytomas than females.

Glioblastomas are often found when people are in their 50s and 60s. The number of U.S. diagnoses is estimated at 10,000 cases per year.

What are the causes of astrocytomas?

We do not know the exact cause of most astrocytomas. Therapeutic irradiation can lead to the development of astrocytomas. Other environmental exposures, though suspected, have not been shown to cause astrocytomas. Some studies have shown evidence of a genetic component in some cases.

What are the symptoms of astrocytomas?

Symptoms are related to the size and location of the astrocytoma. Common symptoms include:

Increased intracranial pressure may lead to abnormal reflexes or weakness on one side of the body.

Last reviewed by a Cleveland Clinic medical professional on 09/05/2018.


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