Astrocytomas

Astrocytomas are tumors that start in glial cells called astrocytes. About 2 out of 10 brain tumors are astrocytomas.

Most astrocytomas can spread widely throughout the brain and blend with the normal brain tissue, which can make them very hard to remove by surgery. Sometimes they spread along the cerebrospinal fluid (CSF) pathways. It is very rare for them to spread outside of the brain or spinal cord.

Astrocytomas are often classified as high grade, intermediate grade, or low grade, based largely on how the cells look under the microscope.

• High grade astrocytomas, known as glioblastomas (or glioblastoma multiforme), are the fastest growing. These tumors make up about two-thirds of astrocytomas and are the most common malignant brain tumors in adults.
• Intermediate-grade astrocytomas, or anaplastic astrocytomas, grow at a moderate rate.
• Low-grade (diffuse) astrocytomas tend to be slow growing, but they can become more aggressive and fast growing over time.
• Some low-grade types called non-infiltrating astrocytomas do not usually grow into nearby tissues and tend to have a good prognosis. These include pilocytic astrocytomas and dysembryoplastic neuroepithelial tumors (DNETs). They are more common in children than in adults.
  
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