What Are Brain Tumors?
Brain tumors are growths of cells within the skull that are not normal.
There are many types of brain tumors in children. They are named for where they occur within the brain and what type of tissue they are made of.
Some brain tumors are cancer (malignant). Others are not (benign).
All types can cause health problems and require treatment.
Tumors that begin in the brain are called primary brain tumors. Brain tumors that arise when cancer spreads to the brain from some other part of the body are called secondary brain tumors. The details given here are about primary tumors.
The effects of brain tumors and the best treatment depend on the type of tumor your child has, where it is in the brain, how much it has spread, your child's age and other aspects of your child's health.
Types of Brain Tumors
There are many types of brain tumors in children. Tumors in the lower part of the brain are called infratentorial. Tumors in the upper part are called supratentorial.
The more common types of brain tumors in children are astrocytoma, brainstem glioma, ependymoma, germ cell tumors and medulloblastoma.
This type of tumor begins in astrocytes, cells that form a network on which nerve cells grow.
Astrocytomas can occur in the cerebellum, which is in the lower brain, or the cerebrum, which is in the upper brain. The cerebrum controls what we know as intelligence - such as thinking, learning and memory.
Often children with astrocytoma have surgery to remove the tumor. They may also receive radiation, chemotherapy or both. Older children with lower-grade (slower growing, less invasive) tumors may have surgery only or receive radiation only.
The lowest part of the brain, which connects to the spinal cord, is called the brainstem. This region controls vital automatic functions, such as our heart rate and breathing.
It also governs many aspects of our basic senses, such as sight and hearing, and movements, including walking and eating.
Brainstem glioma is a tumor that begins in this region. Surgery is not standard treatment because the brainstem is deep in the brain and linked to vital functions. Children with brainstem glioma most often receive radiation, sometimes with chemotherapy.
The brain contains spaces called ventricles where cerebrospinal fluid (CSF) flows. This fluid helps cushion and nourish the brain and spinal cord.
Ependyma is the lining of the ventricles. Ependymal tumors (ependymomas) begin in this lining. They may grow large enough to block the flow of CSF. This type of tumor can occur in the lower or upper part of the brain.
Surgery and radiation, with or without chemotherapy, are the common treatments.
Germ cell tumors
Germ cell tumors arise from sex cells that end up in the brain. These are cells from when the child was a fetus that would normally go on to develop into cells in the testicles or ovaries. But sometimes the germ cells move to other parts of the developing body, including the brain.
Tumors from germ cells typically form in the center of the brain. Surgery and radiation, with or without chemotherapy, are the typical treatments.
Read more about germ cell tumors.
This type of tumor most often begins in the lower back part of the brain called the cerebellum. This area governs movement, balance, posture and coordination.
Doctors treat medulloblastomas with surgery, radiation and chemotherapy. This also may be called a primitive neuroectodermal tumor.
Brain Tumors in Children
Any child may get a brain tumor. Doctors do not know what causes brain tumors in children.
In a small number of children, genetics seem to play a role. For example, some children with the disease neurofibromatosis get tumors in their brain or spinal cord.
Also, children who receive radiation treatment to the head for some other form of cancer may have greater risk for a brain tumor later in life. But most children who have a brain tumor have no clear risk factors.
Brain Tumors at Seattle Children's
Children’s Hospital is the largest pediatric brain tumor center in the Northwest. We treat many children with tumors in the central nervous system (CNS), which includes the brain and spinal cord.
We were one of the first centers to provide care for brain tumors using a team of people from many health fields, called multidisciplinary care.
This is one of the reasons that the National Cancer Institute chose Children’s Hospital as one of only 10 places in the nation to take part in the Pediatric Brain Tumor Consortium (PBTC).
The PBTC studies new methods to diagnose and treat brain tumors in children. Dr. J. Russell Geyer leads our research efforts on CNS tumors with PBTC and the Children's Oncology Group (COG). COG is an international organization of childhood cancer specialists who conduct studies on many forms of childhood cancer.
Our patients who have tumors of the CNS receive care through our special Brain Tumor Clinic. This clinic brings together experts from our staff in neurology, oncology, neurosurgery and related fields.
The team includes pediatric neurosurgeons, pediatric radiologists who specialize in the nervous system, pediatric radiation cancer doctors (oncologists) and many others.
Many of them are known across the nation as leaders in treating childhood brain tumors. They work with children whose brain tumors are cancer as well as children with tumors that are not cancer.
CNS Tumor Survival Rates
Doctors who treat people with cancer use five-year survival rates as a way to measure treatment success. The five-year survival rate means the percentage of patients with the disease who are alive five years after their disease was diagnosed.
For all forms of childhood cancer combined, our five-year survival rate at Children's Hospital is higher than the national average. Our rate is 82%. The national average is 76.4%.
For CNS tumors our rate is more than 15 points higher than the national average. Read more childhood cancer statistics.
Read more about the Brain Tumor Clinic, research and other tumor-related programs and services at Children's.