Cancers of the brain
and nervous system are the most common type of childhood cancer. When discovered
early, these cancers often can be cured.
There are many different types of brain and nervous
system cancers, and doctors categorize them based on where the tumors are, the type
of cells involved, and how quickly they grow.
Here are some of the most common types of brain and nervous system cancers.
Brain Stem Glioma
The brain stem, located deep in the back of the brain, is made up of the midbrain,
pons, and medulla. These parts of the brain control the body's autonomic nervous system
(which is responsible for controlling body processes like breathing, digesting, sweating,
and shivering).
A tumor that develops in any area of the brain stem is called a brain stem
glioma. Tumors in the pons are called pontine gliomas (or
diffuse intrinsic pontine gliomas, DIPG). Pontine gliomas are the most common brain
stem gliomas, and also the most difficult to treat. Tumors
in the midbrain and medulla are less common, but usually easier to treat.
Symptoms of a pontine glioma may start suddenly and get worse very quickly. These
can include:
- double vision
- turning in of one eyeball
- drooping of the eyelid or one side of the face
- trouble swallowing
- trouble speaking and walking
- nausea and vomiting
Midbrain tumors may cause eye symptoms similar to pontine gliomas,
along with headaches and vomiting. This is due to increased pressure in the head caused
by the flow of cerebrospinal fluid being blocked. (Cerebrospinal fluid is a clear,
colorless liquid that delivers nutrients to the brain and spinal cord and "cushions"
them for protection.)
Tumors of the medulla cause swallowing problems
and limb weakness.
Because the brain stem is an area of the brain where surgery can be difficult,
brain stem gliomas are often treated with radiation
therapy (high-energy X-rays that kill cancer cells) and/or chemotherapy.
Ependymoma
Ependymomas are tumors that develop in the brain cells that make cerebrospinal
fluid. They often develop in children under age 5.
Ependymomas are classified according to their location, and most don't spread (metastasize)
to other areas of the body. Those located in the top part of the brain are called
supratentorial ependymomas. Supratentorial ependymomas can cause
nausea, vomiting, and headaches from increased pressure within the brain, as well
as weakness and vision problems.
Ependymomas also can be found in the spinal
cord.
Tumors in the back of the brain are more common. These are called infratentorial
ependymomas. They can cause nausea, vomiting, and headache, and trouble with coordination.
Supratentorial ependymomas sometimes can be
cured by surgery alone. Infratentorial ependymomas usually need much more aggressive
treatment with surgery, chemotherapy, and radiation.