Tumors of the brain may be benign or malignant, and because of the rigid containment of the skull they cause equal havoc by brain compression. There are two main brain tumor types, Meningiomas, arising from the membranes covering the brain and Gliomas , arising from the brain cells.
There are many varieties of latter, such as astrocytomas, oligodendrocytomas, and medulloblastomas, classified according to primary cell type.
For our purpose it is sufficient to note that all these varieties of intacranial tumors may be relatively benign, slow growing, and well encapsulated and, therefore, if other anatomical considerations permit, suitable for clean surgical removal with minimal damage to brain structure, or highly malignant and diffusely infiltrate with little prospect of any neurosurgical success.
However, like every other form of cancer, these highly malignant tumors respond well to radiotherapy, which can offer considerable palliation and even the occasional cure.
Brain tumors can occur at any age, but have a peak incidence in children up to the age 10 and again in the fifth decade of life. Their causation has often been related to previous head injury but the evidence for this is extremely tenuous. The symptoms are increasing headache and interference with some specific brain function, depending upon the anatomical site.