| Cost-effective Screening
for Small Acoustic Neuromas
MRI is the gold standard for detecting acoustic neuromas of any size,
but it is expensive, requires injection of a contrast dye and is not as
widely available as the older ABR (Auditory Brainstem Response) test.
The ABR test, how-ever, while good for medium or large tumors, was missing
30-50% of smaller tumors. This is why it’s so significant that researchers
at the House Ear Institute, in collaboration with Biologic Systems Corporation,
have developed a new test called “Stacked ABR” which detects
up to 95% of smaller acoustic neuromas. As researcher Manuel Don, PhD,
observes in HEI’s newsletter House Calls (Fall, 2003): “.
. . most patients sent for costly and invasive MRI do not have tumors.
The new Stacked ABR provides an effective and cost-efficient way to screen
for small tumors.” The test has been FDA-approved and should be
available soon in audiology centers.
Neurological Surgeons Database
The American Association
of Neurological Surgeons (AANS) offers a free online
database of their physician members. The database is searchable by
area code, state, or physician last name.
“The kind of doctor I want is one who, when he’s not examining
me, is home studying medicine.”
~ George S. Kaufman
Self Help for Hard of Hearing People
SHHH, Self Help for Hard
of Hearing People, publishes a 2003 “Consumers Guide to Hearing
Aids” (24 pp, $5.00).
Write to:
SHHH Publications
7910 Woodmont Avenue, Suite 1200
Bethesda, MD 20814
Monthly meetings of SHHH
are held in Teaneck, Cherry Hill, S.Plainfield, E.Brunswick and Madison.
The Americal Tinnitus Association
has posted an informative, lengthy question & answer discussion about
causes and possible remedies for tinnitus, featuring Michael Seidman,
MD, and Richard Salvi, PhD.
Overlook Hospital in Summit will install a CyberKnife Stereotactic Radiosurgery
System. According to Dr. Louis Schwartz, the director of radiation oncology
at Overlook, the system should be operational by April 2004. At present,
there are only about 13 Cyberknife sites in the USA. The manufacturer
of the system is Accuray,
Sunnyvale, CA.
Brain Awareness Week
Brain Awareness Week (March
15-21) is an international effort organized by the Dana
Alliance for Brain Initiatives to advance public awareness about the
progress, promise and benefits of brain research. To learn of ways in
which you might wish to participate, go to http://www.dana.org/brainweek.
Stopping Tumor Growth
Contrary to the generally accepted notion that radiation kills tumors
by damaging their DNA, researchers at the Memorial Sloan-Kettering Cancer
Center in New York City have presented evidence to show that damage to
the blood vessels that feed the tumor is the key to tumor death by radiation.
In the complicated process known as angiogenesis, tumors recruit endothelial
cells to form the blood vessels needed for tumor growth. But radiation
damages these blood-vessel cells initiating a process called apoptosis,
or “cellular suicide.” As a consequence, the tumor regresses,
shrinks and dies. (See M. Garcia-Barros et al,
“Tumor Response to Radiotherapy Regulated by Endothelial Cell Apoptosis,”
Science, vol. 300, May 16, 2003.)
The MSKCC report is in support of the important finding that different
tumors secrete different “growth factors” that regulate angiogenesis,
the formation of new blood vessels. One such growth factor, VEGF (Vascular
Endothelial Growth Factor), was discovered in 1989 by Napoleone Ferrara,
a biologist at drugmaker Genentech in South San Francisco. Ferrara’s
remarkable discovery led to the development of Genentech’s “Avastin,”
which began human trials in 1997 about a year before Harvard’s Dr.
Judah Folkman announced the discovery of angiostatin and endostatin. “Avastin”
now seems likely to become the first FDA-approved angiogenesis inhibitor
on the market. The drug, in combination with standard chemotherapy, had
great success (May 2003) in trials for metastatic colorectal cancer, and
further testing is currently underway for tumors of the kidney, lung,
pancreas and liver.
In an article entitled “Medical Merlins,” (Forbes, June
12, 2003), science writers Robert Langreth & Zita Moukheiber have
examined the important work of Napoleone Ferrara and other dedicated biologists
and chemists behind the breakthrough drugs coming on the market today.
Appropriately, in the heading for their article, they quote the 1937
Nobel Laureate in Medicine, Albert Szent-Gyorgyi:
“Discovery consists of seeing what everybody has seen and thinking
what noboby has thought.”
Thoughts about Cancer
by Dr. von Eschenbach
Dr. Andrew C. von Eschenbach, director of the National Cancer Institute,
presented the following thoughts about cancer during a meeting with AARP
Bulletin writer Claudia Dreyfus:
“We used to think of cancer as something that just happened to
a person. Now we understand cancer as a long process. It may start with
a genetic predisposition or because of things you were exposed to. The
process continues to the point where it becomes a tumor that spreads and
can take your life. But it’s not something that happens instant-aneously.
By understanding cancer at the genetic, molecular and cellular levels,
we can intervene much more effectively than ever before to preempt the
cancer process. Treatment in the future will be by design, based on your
genes, what chemicals they are expressing, what the specific tumor looks
like, how it works, where it is. . . .
“[As for experiencing cancer]: You just don’t have it and
then forget about it. It becomes a part of your life. Having cancer changes
you. Therefore many of us who are cancer survivors recognize that it’s
not an event that’s over and done with. You have to manage and deal
with some of the after-effects.” (AARP Bulletin,
December 2003)
Whole-Body CT Screening
The findings of the Early Lung Cancer Action Project, reported by researchers
at NY Weill Cornell Center (Lancet, vol.354, 1999), showed that spiral
CT screening of long-time smokers detected four times as many lung cancers
as did ordinary chest x-rays. Of the selected 1000 symptom-free volunteers
60 years or older, malignant disease was detected in 27 (2.7%) by CT,
but in only 7 (0.7%) by x-ray. Clearly, screening individuals at risk
for lung cancer with spiral CT had the potential to save lives. And the
cost of the spiral CT scan was only slightly higher than standard chest
x-ray. So, we may ask: with the introduction of the ultrafast spiral CT
in the 1990s, why not move on to do whole-body CT screening for the detection
of lurking diseases wherever they might be in the body? Thousands of lives
could be saved by spotting symptom- less but life-threatening conditions.
The silent killers within would stand revealed.
Actually, of course, whole-body screening is already here. Entrepreneurs
including radiologists and cardiologists have been quick to utilize the
spiral CT to establish screening centers and advertise a “revolution
in preventive medicine.” It’s been a hot trend in retail health,
much like laser eye surgery. A screening center in Los Angeles offers
the full-body scan for $450 ($849 for 2): neck to hips, 10-15 minutes,
pain-free, quiet, no injections or dyes, no physician referral required,
credit cards accepted. At a center in Pikesville, Maryland, the cost is
$795. In White Plains, NY, patients can get a heart-torso-colon package
for $1495. South Jersey Radiology Associates, with 40 physicians on staff,
offers body screening at offices in Haddonfield, Voorhees, Cherry Hill
and Turnersville. Patient testimonials tell of either life-saving discoveries
or the peace of mind resulting from a “clean scan.”
There’s no question that body scans have saved lives. They’ve
been used in hospital settings for years, especially for people at risk
for heart disease and lung cancer. What’s different recently, as
reported in an excellent article by Janet Raloff in Science News (Sept.
20, 2003), is the appearance of “freestanding, for-profit screening
centers not associated with hospitals.” And further, as observed
in the article by Dr.Michael Brant-Zawadski, a radiologist: “More
and more of [the] scans are for screening rather than just homing in on
the source of symptoms. . . What’s relatively new is who’s
ordering up many of the full-torso scans: symptomfree consumers, usually
without consulting their doctors. Fueling this trend . . . are baby boomers’
preoccupation with wellness, relatively high standard of living, comfort
with new technology, and dissatisfaction with insurance that limits access
to some doctors and procedures.” The new screening centers, says
another radiologist, thrive on the “worried well.”
Consumers need to be careful and ask questions. For one thing, “whole-body
scanning” probably means shoulders to hips. Heads are extra. (Maybe
a MRI scan for the brain would be better?) Also, a reported “clean
scan” is not necessarily the same thing as a clean bill of health.
Some significant diseases such as colon cancer, diabetes and hypertension
don’t show up on routine body scans, and most abdominal organs such
as kidneys image poorly unless a contrast dye is injected. Most cancers,
moreover, tend to appear sporadically and can be missed without frequent
screening. The report of a “clean scan,” we see, could lead
to a false sense of security, such that an individual may ignore subtle
symptoms of illness and fail to check with a physician.
There is also the problem that the high quality imaging of the spiral
CT is very likely to reveal suspicious nodules that can result in expensive
and risky follow-up procedures (biopsies, exploratory surgeries, further
scans) even though no disease may actually be found. Too often these harmless
abnormalities, called “false-positives,” become an anxiety-producing
feature of preventive screening. One estimate is that as many as 80% of
abnormalities detected by whole-body CT may not be life-threatening.
For reasons such as these, critics of the new screening centers see
the need for the adoption of guidelines to protect consumers. For example,
screening centers should: 1) inform consumers about body organs that do
not image well; 2) make consumers fully aware of the expense and risks
of possible follow-up procedures; 3) provide information about the frequency
of screening needed to catch certain diseases as they may develop; and
4) warn that a potentially serious condition may actually go undetected.
For its part, the U.S. Food & Drug Administration (www.fda.gov)
would want to include a warning about excessive radiation exposure. The
initial low-dose radiation of the spiral CT is actually not much greater
than standard x-ray, but screening centers would need to advise consumers
that follow-up testing could require several focused higher-dose CT scans.
The FDA, as well as professional organizations such as the Radiological
Society of North America (www.radiologyinfo.org), have expressed concern
that cumulative radiation from numerous screening exams over time carries
the risk of inducing cancers later in life.
British researchers, for example, have just recently reported on data
which they believe shows that the risk of developing cancer from x-rays
and CT scans has increased in the United States since 1981 from 0.5% to
0.9%. For the 15 developed countries surveyed for 1991-1996, the risk
was lowest in Britain (0.6%), which uses the tests the least, and highest
in Japan (3.2%), where frequency of exposure to the tests is greatest.
(Lancet, January 31, 2004)
The FDA has stated that “if large numbers of healthy people now
start to receive radiation exposure from whole-body CT screening for questionable
benefit, the overall effect on public
health could be detrimental.” The RSNA notes: “These concerns
should not preclude CT scanning when a physician has recommended a diagnostic
examination for a patient with symptoms of disease.”
¨Note: The American College of Radiology (ACR) advises that the
effective dose for a conventional chest x-ray is 0.1 millisieverts (0.1mSv),
which is equivalent to the amount the average person receives over a 10-day
period from naturally occurring radioactive materials such as radon gas,
rays from the sun, rocks and certain foods. The average person receives
about 3 mSv of such natural “background radiation” each year.
A standard chest CT scan involves a radiation dose of about 8 mSv. The
ACR points out that MRI images of soft-tissue structures such as heart,
lungs, liver and other organs are clearer and more detailed than with
CT. Moreover, since MRI uses radiofrequency waves and a strong magnetic
field rather than x-rays, exposure to radiation is avoided. MRI scans
are more expensive and take longer than CT.
Center for Humanistic Medicine
The Healthcare Foundation of New Jersey has announced a grant of $3.2
million to establish a Center for Humanistic Medicine at Newark’s
UMDNJ - New Jersey Medical School. The center will focus on training doctors
in compassionate care and in becoming medical and scientific experts on
humanism in medicine. Russell Joffe, dean of the medical school, has noted
that, “when the center opens in the fall, it will coincide with
the unveiling of a new medical school curriculum that will equip students
to be better prepared to practice in today’s rapidly changing health-care
environment.” (Newark Star Ledger, January
13, 2004)
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