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Information about Brain Tumors
Disclaimer: This information is for educational purposes only. We cannot assume responsibility for its accuracy. Please, obtain information about your condition from your Doctor. The Brad Kaminsky Foundation does not endorse any service, treatment, institution or physician
Types of Brain Tumors
Primary Brain Tumors
Tumors that begin in brain tissue are known as primary brain tumors.
(Secondary tumors that develop when cancer spreads to the brain are
discussed in the Secondary Brain Tumors section.) Primary brain
tumors are classified by the type of tissue in which they begin. The
most common brain tumors are gliomas, which begin in the glial
(supportive) tissue. There are several types of gliomas: Astrocytomas
arise from small, star-shaped cells called astrocytes. They may grow
anywhere in the brain or spinal cord. In adults, astrocytomas most
often arise in the cerebrum. In children, they occur in the brain stem,
the cerebrum, and the cerebellum. A grade III astrocytoma is
sometimes called anaplastic astrocytoma. A grade IV astrocytoma is
usually called glioblastoma multiforme.
Brain stem gliomas occur in the
lowest, stemlike part of the brain. The brain stem controls many vital
functions. Tumors in this area generally cannot be removed. Most brain
stem gliomas are high-grade astrocytomas. Ependymomas usually
develop in the lining of the ventricles. They may also occur in the
spinal cord. Although these tumors can develop at any age, they are
most common in childhood and adolescence. Oligodendrogliomas
arise in the cells that produce myelin, the fatty covering that protects
nerves. These tumors usually arise in the cerebrum. They grow slowly
and usually do not spread into surrounding brain tissue.
Oligodendrogliomas are rare. They occur most often in middle-aged
adults but have been found in people of all ages. There are other types
of brain tumors that do not begin in glial tissue. Some of the most
common are described below: Medulloblastomas were once thought to
develop from glial cells. However, recent research suggests that these
tumors develop from primitive (developing) nerve cells that normally do
not remain in the body after birth. For this reason, medulloblastomas
are sometimes called primitive neuroectodermal tumors (PNET). Most
medulloblastomas arise in the cerebellum; however, they may occur in
other areas as well. These tumors occur most often in children and are
more common in boys than in girls. Meningiomas grow from the
meninges. They are usually benign. Because these tumors grow very
slowly, the brain may be able to adjust to their presence; meningiomas
often grow quite large before they cause symptoms. They occur most
often in women between 30 and 50 years of age. Schwannomas are
benign tumors that begin in Schwann cells, which produce the myelin
that protects the acoustic nerve--the nerve of hearing. Acoustic
neuromas are a type of schwannoma. They occur mainly in adults.
These tumors affect women twice as often as men.
Craniopharyngiomas develop in the region of the pituitary gland near
the hypothalamus. They are usually benign; however, they are
sometimes considered malignant because they can press on or
damage the hypothalamus and affect vital functions. These tumors
occur most often in children and adolescents. Germ cell tumors arise
from primitive (developing) sex cells, or germ cells. The most frequent
type of germ cell tumor in the brain is the germinoma. Pineal region
tumors occur in or around the pineal gland, a tiny organ near the
center of the brain. The tumor can be slow growing pineocytoma) or
fast growing (pineoblastoma). The pineal region is very difficult to
reach, and these tumors often cannot be removed. Secondary Brain
Tumors Metastasis is the spread of cancer. Cancer that begins in other
parts of the body may spread to the brain and cause secondary
tumors. These tumors are not the same as primary brain tumors.
Cancer that spreads to the brain is the same disease and has the
same name as the original (primary) cancer. For example, if lung
cancer spreads to the brain, the disease is called metastatic lung
cancer because the cells in the secondary tumor resemble abnormal
lung cells, not abnormal brain cells. Treatment for secondary brain
tumors depends on where the cancer started and the extent of the
spread as well as other factors, including the patient's age, general
health, and response to previous treatment.
The Brad Kaminsky Foundation for Brain Tumor Research 20227 Catlett Place Ashburn, VA 20147 (703) 729-9897 E-mail DNL1231@aol.com |
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