THE NATIONAL
INSTITUTES OF
HEALTH
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National Institute of
Neurological
Disorders and Stroke |
Embargoed for release:
Wednesday, June 16, 1999, 5:00 p.m. EDT |
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information,
contact:
Marcia Vital at 301-496-5751
NCI Press Office 301-496-6641
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Researchers Develop
Better Means to Diagnose Adrenal
Gland Tumors
A newly developed blood test
to detect potentially deadly tumors that form
in the adrenal glands has been shown to be significantly more sensitive
than
traditional diagnostic tests. The new test provides earlier and more
accurate
diagnoses of these tumors in patients with an inherited predisposition
to
develop them, possibly preventing complications or death. The study, led
by researchers at the National Institute of Neurological Disorders and
Stroke
(NINDS) and the National Cancer Institute (NCI), will appear in the June
17, 1999, issue of The New England Journal of
Medicine.1
"Although rare, these tumors
are clinically important because they must be
excluded as a surgically curable cause of hypertension in many of the
people
who develop high blood pressure," says Graeme Eisenhofer, Ph.D., a
researcher
in the Clinical Neurocardiology Section of the NINDS, and lead author of
the study. "If the tumors are not diagnosed and removed, they can have
potentially catastrophic consequences for the patient."
The mainly benign tumors,
called pheochromocytomas, are sometimes found in
patients with Von Hippel-Lindau (VHL) disease, a familial cancer
syndrome
with neurologic complications in which affected individuals inherit a
predisposition to develop tumors in a number of organs, including the
adrenal
glands that sit atop the kidneys.
"Pheochromocytoma can occur
in VHL patients as young as 8 years of age. Deaths
from unsuspected adrenal gland tumors have been reported in young
children
in these families and it is important to make the diagnosis early so
that
surgical intervention can be performed," said W. Marston Linehan, M.D.,
NCI’s Chief of Urologic Surgery.
A patient who develops
pheochromocytomas for any reason is at risk for dangerous
and unpredictable surges in blood levels of certain adrenal gland
hormones
that regulate blood pressure and which are responsible for the so-called
"fight or flight" responses to stress. The surges in hormones and
resulting
spikes in blood pressure put the patient at risk for heart attack,
stroke,
hemorrhage, or sudden death.
Currently, the most reliable
tests for pheochromocytomas use imaging
technologies, such as MRI (magnetic resonance imaging), which can be
time-consuming and expensive and which do not necessarily identify a
tumor
as a pheochromocytoma. Confirmatory biochemical tests are required for
accurate
diagnosis. Several biochemical tests are available which measure blood
and
urine levels of the adrenal gland hormones. But in many cases these
tests
are not accurate, because some pheochromocytomas do not release the
adrenal
hormones regularly or in significant amounts.
Drs. Eisenhofer, Linehan,
and their colleagues found that these tumors contain
an enzyme that continually transforms the adrenal hormones epinephrine
and
norepinephrine into the chemicals metanephrine and normetanephrine. Only
pheochromocytomas produce these chemicals consistently in any
significant
quantity. Dr. Eisenhofer and colleagues hypothesized that measurements
of
blood levels of these two chemicals would give a more accurate diagnosis
of pheochromocytomas.
Altogether, they measured
the amounts of normetanephrine and metanephrine
in 26 patients with VHL disease and 9 patients with multiple endocrine
neoplasia
type 2 (MEN2), another rare genetic disease characterized by
pheochromocytomas.
Use of the new test detected 97 percent of the tumors, whereas the other
tests detected only 47 to 74 percent of tumors. Although particularly
useful
in diagnosis of tumors in VHL disease and MEN2, the test also shows
promise
for improved diagnosis of pheochromocytomas in the much larger
population
of patients with high blood pressure where the tumor needs to be
excluded.
NINDS and NCI are part of
the National Institutes of Health in Bethesda,
Maryland. The NINDS is the nation’s premier supporter of research
on the brain and nervous system and will celebrate its 50th anniversary
in
the year 2000. For more news and information about cancer, visit
NCI’s Web site for patients, the public, and the mass media at
http://rex.nci.nih.gov
This release will be posted
on EurekAlert! at http://www.eurekalert.org
READ THE ARTICLE:
Researchers Develop
Better Means to Diagnose Adrenal
Gland Tumors
1Eisenhofer, G.;
Lenders, J.W.M.; Linehan, W.M.; Walther, M.M.;
Goldstein, D.S.; Keiser, H.R. "Plasma normetanephrine and metanephrine
for
detecting pheochromocytoma in Von Hippel-Lindau disease and multiple
endocrine
neoplasia type 2." The New England Journal of Medicine, Vol. 340,
No. 24, June 17, 1999, pp. 1872-1879.
National Institute of
Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
© 2000 – 2013 Pheochromocytoma Organization
Pheochromocytoma Support Group
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