Types of Primary & Secondary Brain Tumors

Brain tumors are classified into two basic groups, primary & secondary brain tumors.

• Primary Brain Tumors

Tumors which originate within the brain tissue are called primary brain tumors. These are further classified by the type of tissue they arise in. Gliomas are the most common type of brain tumors which begin in the supportive tissue. Some types of gliomas include the following.

• Astrocytomas – These arise from small star-shaped cells known as astrocytes & which can grow anywhere in brain. Astrocytomas in adults usually arise in cerebellum, & they occur in the cerebellum, cerebrum & brain stem in children. Grade III astrocytomas are sometimes known as anaplastic astrocytoma & Grade IV astrocytomas as glioblastoma multiforme.


• Oligodendrogliomas – These arise within the cells producing myelin, the fatty covering protecting nerves. These are usually located in cerebrum & grow slowly without spreading into surrounding brain tissue.


• Ependymomas – These are usually found to develop in lining of ventricles. Also occurring in the spinal cord, ependymomas can develop at any age & are the most common among children & adolescents.

Other Types of Primary Brain Tumors

• Meningiomas – These grow from meninges & are usually benign. Since they grow very slowly brain can adjust to their presence at times. However, meningiomas can grow quite large before they display symptoms. Moreover, these occur most often in women between 30 – 50 years of age.


• Schwannomas – These are generally benign tumors which arise within Schwann cells producing myelin. Acoustic neuromas are a type of schwannoma which occur mainly in adults. Schwannomas affect women twice as often as they occur in men.


• Craniopharyngiomas – These tumors develop in the region of pituitary gland near hypothalamus. Although generally benign, they are sometimes considered malignant as they can press upon or damage hypothalamus & affect vital functions. Craniopharyngiomas most often occur among children & adolescents.


• Germ Cell Tumors – Germ cell tumors generally arise from sex cells which are developing (primitive) or germ cells itself. Germinoma is the most frequent type of germ cell tumor.


• Pineal Region Tumors – These are usually occurring around the pineal gland which is a tiny organ located at the center of the brain. These tumors which are slow growing are known as pineocytoma & fast growing pineoblastoma. Since pineal region is very difficult to reach through brain tumor surgery & most often these tumors cannot be removed.

• Secondary Brain Tumors

These types of brain tumors are usually caused from cancers which originate in other parts of the body. This spread of cancer within the body is known as metastasis. Cancer which metastasizes & spreads to the brain is the same disease & therefore keeps the original primary cancer name. Like for example, lung cancer which spreads to brain is called metastatic lung cancer since cells in the secondary tumor resemble abnormal lung cells & not brain cells. Moreover, brain tumor treatment for secondary brain cancers usually depends upon where the cancer has originated & upon the extent of spread along with factors like patient’s general health, age & response to prior treatments.