There are over 120 different types of brain tumors. The World Health Organization (WHO) organises brain tumors with a grading system to standardize communication across heath networks across the globe. The aim is to plan treatment and predict outcomes more accurately and in an systematic fashion.
However, based on site of origin, there are two types of brain tumors:
a. Primary brain tumors originate in brain tissue and tend to stay there.
b. Secondary brain tumors are more common. Generally, these cancers start somewhere else in the body and travel to the brain. Furthermore, lung, breast, kidney, colon, prostate and skin cancers are among the most commonest primary cancers that metastasize to the brain.
Moreover, some brain tumors contain cancer cells and others don’t.
- Benign brain tumors are free from cancer cells. They grow slowly, and are curable. Besides, they seldom spread to the surrounding brain tissue. They can be life-threatening depending on the location of the tumor.
- Malignant brain tumors contain cancer cells. The growth rates differ, but cells can invade healthy brain tissue surrounding it. These seldom spread beyond the brain or spinal cord.
Types of Brain Tumors
In adults, the most common types of brain cancer are:
- Astrocytomas. These usually start in the part of the brain that occupies most space the cerebrum. They cause seizures or shifts in behavior.
- Meningiomas. These are the commonest primary brain tumors in adults. They are most likely to occur in 70s or 80s . They start in the meninges, the lining of the brain. They can be of grades 1, 2, or 3. They are benign and metastasis is rare.
- Oligodendrogliomas. These arise in the cells that make the covering that protects nerves. They are usually of grades 1, 2, or 3. They usually grow slowly and don’t spread to nearby tissue.
Among children, the most common tumor types are:
- Medulloblastoma: The tumor usually arises in the cerebellum. It is sometimes called a primitive neuroectodermal tumor. It is grade IV.
- Grade I or II astrocytoma: In children, this low-grade tumor occurs anywhere in the brain. The most common astrocytoma among children is juvenile pilocytic astrocytoma. It’s grade I.
- Ependymoma: It arises from cells that line the ventricles or the central canal of the spinal cord. It’s most commonly found in children and young adults. It can be grade I, II, or III.
- Brainstem glioma: The tumor occurs in the lowest part of the brain. It can be a low-grade or high-grade tumor. The most common type is diffuse intrinsic pontine glioma.
Furthermore, the common ones of brain tumor are:
- Pilocytic Astrocytoma (grade I)
- Diffuse Astrocytoma (grade II)
- Anaplastic Astrocytoma (grade III)
- Glioblastoma Multiforme (grade IV)
- Oligodendroglioma (grade II)
- Anaplastic Oligodendroglioma (grade III)
- Ependymoma (grade II)
- Anaplastic Ependymoma (grade III)
6. Schwannoma (neuroma)
7. Pituitary adenoma
8. Pinealoma (pineocytoma, pineoblastoma)
Furthermore, read about the stages of brain tumor.