CD-ROM Today (UK) (Spanish) 15/CDRT.iso/dp/0350/03501.txt

Text File | 1994-01-17 | 11KB | 235 lines

$Unique_ID{BRK03501}
$Pretitle{}
$Title{Astrocytoma, Malignant}
$Subject{Astrocytoma Malignant Giant Cell Glioblastoma Anaplastic Astrocytoma
Spongioblastoma Multiforme Astrocytoma grades 3-4}
$Volume{}
$Log{}

Copyright (C) 1986, 1988, 1989 National Organization for Rare Disorders, Inc.

277:
Astrocytoma, Malignant

** IMPORTANT **
It is possible the main title of the article (Malignant Astrocytoma) is
not the name you expected.  Please check the SYNONYMS listing to find the
alternate names and disorder subdivisions covered by this article.

Synonyms

     Giant Cell Glioblastoma
     Anaplastic Astrocytoma
     Spongioblastoma Multiforme
     Astrocytoma, grades 3-4

General Discussion

** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.


Malignant Astrocytoma is an infiltrating, primary brain tumor, with
tentacles that may invade surrounding tissue.  This provides a butterfly-like
distribution pattern through the white matter of the cerebral hemispheres.
The tumor may invade a membrane covering the brain (the dura), or spread via
the spinal fluid through the ventricles of the brain.  Spread of the tumor
(metastasis) outside the brain and spinal cord is rare.

Symptoms

Malignant Astrocytoma grows by spreading into normal tissue.  The first
symptoms of this tumor are commonly those of increased cranial pressure.
This pressure results from the inability of the bones of the skull to expand
to accommodate the growing tumor.  A headache which is not localized and is
worse in the morning, may be accompanied by vomiting.  Nausea is rarely
present.  Subtle personality changes may precede these symptoms.

Malignant Astrocytoma may occur in any area of the cerebral hemispheres,
but are most common in the frontal, temporal and parietal lobes, causing
symptoms specific to each location.

Frontal lobe tumors usually cause intellectual disabilities, such as
memory impairment.  Patients with this kind of tumor may show little or no
emotions (flat personality effect).  Symptoms may also include seizures
(convulsions) and paralysis (hemiplegia) on the side of the body opposite the
location of the tumor.

Temporal tumors initially present fewer symptoms, but may include
seizures, language interpretation disturbances, and motor disturbances such
as lack of coordination of body parts.

Parietal tumors are usually characterized by writing disturbances
(agraphia), sensory changes such as tingling sensations (paresthesias),
spatial disorientation or loss of awareness of the position of parts of the
body, and seizures.

Causes

The cause of Malignant Astrocytoma, like most brain tumors, is unknown.
Cases of familial tumors have been reported, but a hereditary mode of
transmission has not yet been proven.

Occupational chemical factors have been associated with some tumors such
as employment in rubber manufacturing industries, vinyl chloride exposure,
and farmers exposed to chemical sprays.  It has been suggested that children
exposed to lead or who have used barbiturates may be at a higher risk to get
Malignant Astrocytoma.

Recent research suggests that astrocytoma may be caused by a rare virus,
but more studies are needed to prove or disprove this theory.

Affected Population

Malignant Astrocytoma occurs most often in people between the ages of 48 and
60 years, although it can also affect pre-teenage children.  It affects twice
as many males as females, and whites more frequently than nonwhites.  Males
with type A blood appear to be at a higher risk.

Sixty-five to seventy percent of patients with Astrocytoma survive 1
year, and forty percent 2 years.  Many survive longer.

Related Disorders

Glioblastoma Multiforme is similar to Malignant Astrocytoma, but it is an
even more malignant tumor.  (For more information on this disorder, choose
"glioblastoma multiforme" as your search term in the Rare Disease database.)

Therapies:  Standard

Treatment for this disorder may include surgery, radiation, or chemotherapy.

SURGERY--The treatment of choice for accessible Malignant Astrocytoma
tumors is surgery.  Accessible tumors are those which can be operated on
without causing unacceptably severe damage to of the brain.  If the tumor is
not accessible, a biopsy and steroid medications to control swelling may be
recommended instead of surgical removal.  The biopsy results may indicate a
tumor that is amenable to other treatment methods.  A subtotal decompressive
resection, or partial removal of tumor tissue, may be performed to decrease
symptoms and also improve the chances for other therapies to be effective.
In situations where the tumor has extensively invaded the brain, either of
these therapies is used primarily for relief of symptoms.

If aggressive surgery or total resection is undertaken, the surgeon will
attempt to remove all identifiable tumor, often using an operating microscope
to better see tumor margins.  In some cases, a laser and/or ultrasonic
aspirator is used as well.  Laser microsurgery has the advantage of being
able to remove, by vaporization, some tissue beyond the tumor's border with
the hope of removing microscopic tumor infiltrates with a minimal amount of
damage to normal tissue.

Astrocytomas frequently cannot be totally removed because the spreading
tumor, too small for the surgeon to see, is usually present in the
surrounding area.  Aggressive resection reduces the number of tumor cells to
a level where radiation therapy and chemotherapy can be more effective.  If
the tumor recurs, a second or even third operation may be performed.

RADIATION--External radiation is usually recommended following surgery.
It begins almost immediately, both to the tumor and to the entire brain.
Whole brain irradiation is administered because the Astrocytoma tends to
infiltrate widely.  After radiation has reduced the number of tumor cells,
chemotherapy is administered in an attempt to destroy any cells that remain.
Chemotherapy may also be given during the course of radiation treatment.

CHEMOTHERAPY--The drugs used in chemotherapy are cytotoxins, or cell
poisons, which are capable of destroying cells.  Cytotoxins are not
completely tumor-cell specific, so they may also cause damage to normal
tissue.  The type of chemotherapeutic drug selected is determined by a
neurooncologist who examines the grade of tumor, previous treatment and
current health status of the individual with Malignant Astrocytoma.  A neuro-
oncologist is a physician who has been specially trained and has experience
in treating brain tumors.  The most commonly used drugs are BCNU and CCNU.
Other drugs may be prescribed on an experimental basis.

Therapies:  Investigational

One of the new experimental techniques for treatment of Malignant Astrocytoma
is brachytherapy, also called "interstitial radiation" or "seeding".  Via a
surgical procedure, radioactive pellets of as Iodine, Iridium or Gold
isotopes are implanted directly into the tumor.  Brachytherapy is used
primarily in recurrences when the tumor is confined to one side of the brain
and measures less than 2 1/2 inches (about the size of an egg).

Other investigational therapies include use of 1) cell radiosensitizers
to increase the effectiveness of radiation; 2) different types of radiation
such as neutrons, heat (hyperthermia) and light (photoradiation); 3)
intraoperative radiation; and 4) hyperfractionation.  These treatments are
ongoing research projects which are being clinically tested against Malignant
Astrocytoma cells.

Immunotherapy aims to stimulate the body's defenses against the tumor.
Using drugs such as interferon, levamisole, interleukin-2 and thymosine, and
BCG, it is hoped that the body's own immune system can be stimulated to fight
the tumor.

A multitude of new drugs and drug combinations are being tested for
effectiveness against Astrocytoma.   Other research seeks to develop better
methods of drug delivery, such as direct intra-arterial administration and
blood brain barrier disruption to increase the amount of anticancer drug
reaching brain tissue.

A new orphan drug and delivery system is being tested for the treatment
of Astrocytoma and Glioblastoma.  During surgery to remove the brain tumor, a
biodegradable wafer containing a cancer fighting drug (BCNU) is implanted at
the sight of the tumor.  At least 220 patients are needed for a clinical
trial of this drug.  Those interested should have their physician contact Dr.
James Kenealy, Nova Pharmaceutical Corp., 6200 Freeport Centre, Baltimore, MD
21224 or phone [phone].

This disease entry is based upon medical information available through
June 1989.  Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.

Resources

For more information on Malignant Astrocytoma, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     Association for Brain Tumor Research
     2910 West Montrose Ave.
     Chicago, IL 60618
     [phone]

     American Cancer Society
     1599 Clifton Rd., NE
     Atlanta, GA  30329
     [phone]

     NIH/National Institute of Neurological Disorders & Stroke (NINDS)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]
     [phone]

     NIH/National Cancer Institute (NCI)
     9000 Rockville Pike, Bldg. 31, Rm. 1A2A
     Bethesda, MD 20892
     (800) 4-CANCER

The National Cancer Institute has developed PDQ (Physician Data Query), a
computerized database designed to give the public, cancer patients and
families, and health professionals quick and easy access to many types of
information vital to patients with this and many other types of cancer.  To
gain access to this service, call:
     Cancer Information Service (CIS)
     1-800-4-CANCER
     In Washington, DC and suburbs in Maryland and Virginia, 636-5700
     In Alaska, 1-800-638-6070
     In Oahu, Hawaii, [phone] (Neighbor islands call collect)

References

ABOUT GLIOBLASTOMA MULTIFORME AND MALIGNANT ASTROCYTOMA; D. P. Hesser, et.
al., eds.;  Association for Brain Tumor Research, 1985.