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All about brain tumor primary brain tumors secondary brain tumors types of brain tumors causes of brain tumor risk factors for brain tumors complications of brain tumor symptoms of brain tumors diagnosing brain tumor brain tumor treatment

What types of brain tumors are there?

About half of all primary brain tumors are known collectively as gliomas. They are cancerous forms of glial cells, which are the building-block cells of the connective, or supportive, tissue in the central nervous system. There are several glial cells

types from which gliomas form and are named:
  • Astrocytomas are primary brain tumors derived from astrocytes, which are star-shaped glial cells. Astrocytes provide nutrients, support, and insulation for nerve cells and are one of the primary neurologic cells in the body.
  • Oligodendrogliomas develop from oligodendrocyte glial cells. These tissues form the protective coatings around nerve cells. Although these tumors were thought to represent about 5% of all gliomas, more recent evidence suggests they may comprise about 20% of gliomas. Pure oligodendrogliomas, however, are rare and in most cases they occur in mixed gliomas.
  • Ependymomas are derived from ependymal cells. These cells line the ventricles (fluid-filled cavities) in the lower part of the brain and the central canal of the spinal cord. They constitute about 6% of all gliomas.
  • Mixed Gliomas contain a mixture of malignant gliomas. About half of these tumors contain both cancerous oligodendrocytes and astrocytes.

Some brain tumors are categorized by their location in the brain. Such tumors often contain gliomas but are also frequently a mixture of different cell types.

  • Meningiomas. Meningiomas are usually benign tumors that develop in the membranes that cover the brain and spinal cord (the meninges). They are not technically classified as brain tumors but they have similar symptoms and develop within the brain, and so in practical terms, they are considered to be brain tumors. In fact, they comprise 20% of all primary brain tumors. They occur more often in women than in men. Most grow very slowly, and the majority of people who have them never know they are present. Malignant forms called anaplastic meningiomas and hemangioperictyomas are less common and are difficult to remove surgically.
  • Cerebellar Astrocytomas. Gliomas that develop inside the brain usually occur in the cerebral hemispheres (the right and left sides of the brain). In such cases, they are referred to by their location, cerebellar astrocytomas.
  • Brain Stem Gliomas. Brain stem gliomas develop in the lowest portion of the brain. The brain stem connects the cerebrum (the higher centers of the brain) to the spinal cord. The brain stem is thought to be the primitive brain because it controls the most basic functions.
  • Medulloblastomas. Medulloblastomas are always located in the cerebellum, which is at the base and toward the back of the brain. They represent about 3% of all brain tumors.
  • Pituitary Tumors. Pituitary tumors comprise about 10% of primary brain tumors and are benign, slow-growing masses in the pituitary gland.
  • Other Brain Tumor Locations. Optic nerve gliomas occur in the optic nerve, which is located behind the eye. Acoustic neuromas make up 7.5% of brain tumors.

More information on brain tumor

What is brain tumor? - Brain tumors are abnormal growths made up of cells whose growth and division are no longer under the control of the body.
What are primary brain tumors? - A primary malignant brain tumor is one that originates in the brain itself. Primary brain tumors are named due to the cell types.
What are secondary brain tumors? - A secondary (metastatic) brain tumor occurs when cancer cells spread to the brain from a primary cancer in another part of the body.
What types of brain tumors are there? - About half of all primary brain tumors are known collectively as gliomas. Some brain tumors are categorized by their location in the brain.
What causes brain tumors? - The majority of brain tumors have abnormalities of genes involved in cell cycle control, causing uncontrolled cell growth.
What're the risk factors for brain tumors? - Risk factors for brain tumors include age, environmental or occupational risk factors, diseases associated with brain tumors.
What're the complications of brain tumors? - Brain tumors may lead to an emergency complication known as hydrocephalus. A brain tumor can cause temporary or permanent brain damage.
What're the symptoms of brain tumors? - Symptoms of brain tumors vary depending on the size and location of tumor. Many symptoms are related to an increase in pressure in or around the brain.
How is brain tumor diagnosed? - Brain tumor is diagnosed through a combination of symptoms and evaluation of neurological functions.
What's the treatment for brain tumors? - The approach for treating brain tumors is to reduce the tumor as much as possible using surgery, radiation treatment, chemotherapy, or investigative procedures.
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