|Type of Tumor||Cell of Origin||Function|
|Oligodendroglioma||Oligodendrocyte||Produces a substance called myelin, which covers the nerves and helps information to travel quickly between the brain and other parts of the body.|
|Ependymoma||Ependyma||Lines the ventricles and aids in the circulation of cerebrospinal fluid.|
|Meningioma||Meninges||Covers and protects the brain and spinal cord.|
|Lymphoma||Lymphocyte||Part of the immune system, the body’s primary defense against infection and foreign substances.|
|Schwannoma||Schwann cell||Produce the myelin that protects the acoustic nerve, the nerve of hearing.|
|Medulloblastoma||Primitive neuroectodermal||Cell or Primitive nerve tumor (PNET) These cells normally do not remain in the body after birth.|
Cancer from other parts of the body can spread to the brain and cause secondary tumors through a process called Metastasis. Although it is possible for cancer from anywhere in the body to spread to the brain, it happens most often with cancers of the breast and lung. The cells of a metastatic brain tumor resemble the cells of the organ where the tumor started, not brain cells. For example, if a tumor starts in the breast and spreads to the brain, the cells of the brain tumor will resemble abnormal breast cells, not abnormal brain cells.