A brain tumor is a mass of cells growing unnecessarily or abnormally in the brain. These tumors can be benign or malignant. Benign tumors are made up of slow growing cells that rarely spread and that have a distinct border. Benign tumors can be life threatening if they are located in a vital area.
Malignant tumors grow rapidly and are life threatening.
They can spread to other parts of the body, destroying healthy tissue. If the tumor starts in the brain, it is known as a primary brain tumor, such as glioblastoma mutiforme, astrocytoma and medulloblastoma. If cancer has started elsewhere in the body and spread to the brain, then it is known as a metastatic brain tumor. More than 185,000 people are diagnosed each year with brain tumors. Of that number, about 35,000 have primary brain tumors and about 150,000 have metastatic brain tumors.