Move
Over, PSA
A simpler, more precise blood test
could reduce unneeded treatments.
Prepare for a major leap forward in detecting prostate
cancer. If all goes well during ongoing trials, says
Robert Getzenberg, “a simple blood test” could
vastly outperform the current technique, popularly
known as the PSA test. The new blood test could spare
more than a million men per year from the pain of multiple
biopsy needles.
In the last several years, Getzenberg and colleagues
here have learned how to track a new marker for the
presence of prostate cancer. Traditional tracking of
prostate-specific antigen (PSA) has helped save lives
over the past 25 years, says Getzenberg, but PSA scores
are, at best, a very rough gauge for the presence of
cancer.
Consider that about 1.3 million men found to have
high PSA levels will be scheduled for prostate biopsies
this year, but only 19 percent will actually have prostate
cancer. Perhaps worse, about 15 percent of men who
do have prostate cancer will go undetected because
their PSA levels failed to reach the threshold for
a biopsy.
The new test screens for a protein known as early
prostate cancer antigen-2 (EPCA-2). In a study published
in April’s Urology—based on groups of patients
with and without the disease—the EPCA-2 test
accurately detected prostate cancer in 94 percent of
men with the condition, with just a 3 percent rate
of false positives. In a smaller sampling of 18 men
who had prostate cancer despite low PSA levels, the
EPCA-2 assay found it in 14 of them.
This more definitive test could have enormous impact. “We’re
probably overtreating many men for prostate cancer
today,” says Getzenberg, who directs research
at the Brady Urological Institute. The new test could
also flag men with prostate cancer whose conditions
were missed through PSA screening.
And the EPCA-2 test appears to provide an added value:
It can tell when the cancer is confined inside the
prostate or has spread beyond its borders; the latter
signals a more aggressive form of the disease that
calls for more forceful treatment.
In either case, early treatment can help beat the
disease, which currently takes more than 27,000 lives
each year.
If the new test is approved, Getzenberg expects its
early use would be similar to that of the PSA test.
He says patients at risk—all men over 40 or those
with a family history of prostate cancer—will
likely still undergo a digital rectal exam to detect
abnormalities in the gland. Tests for both PSA and
EPCA-2 levels would follow. But some years from now,
Getzenberg believes, the new test will supplant the
value of traditional PSA testing. “If our data
hold up in the current multicenter trials,” he
says, “you would easily throw out PSA."
Ramsey Flynn
“Neurosurgery” on the Pancreas
For benign tumors, the Whipple may be overkill.
 |
 |
 |
 |
| >Andersen, with his ultrasonic wonder |
|
|
When a swollen foot prompted Colorado Springs radiologist
Michael Fox to visit his physician, the doctor ordered
a CT scan to see if a lymph node abnormality might
be the culprit. It wasn’t, but to Fox’s
consternation, the imaging turned up a 4-centimeter
mass on the head of his pancreas.
Fox spent the next few weeks researching his options
and having further tests done. Everyone agreed the
tumor looked benign. And with a single exception, his
colleagues said his only option was the Whipple procedure.
The extensive surgery would remove not only the head
of his pancreas but his gallbladder, common bile duct
and part of his duodenum as well. Only the surgeon
in his group practice, citing “a lot of morbidity
and mortality,” advised against the Whipple.
Fox hit the Web in search of an alternative and turned
up information about Hopkins’ Dana Andersen,
who has pioneered a “less-than-a-Whipple” procedure
that spares the duodenum.
Andersen, chief of surgery at Johns Hopkins Bayview
Medical Center, understands why most physicians hear
pancreatic lesion and immediately think Whipple. Although
less drastic operations were introduced in the 1980s
for benign and premalignant tumors or chronic inflammation
on the head of the pancreas, they’re rarely performed
in the United States. Andersen believes that should
change. He’s developed a technique for excavating
the central core of the pancreatic head and removing
the proximal main pancreatic duct while preserving
the posterior capsule and neck of the pancreas. Because
he’s resecting a smaller portion of the pancreas
and none of the small intestine, morbidity is lower
and patients are unlikely to have subsequent digestive
problems or diabetes.
Still, Andersen says, “the pancreas is very
vascular, so coring out the head is technically challenging.” To
do that safely, he uses an ultrasonic aspirator and
dissector, an instrument more commonly found in the
hands of neurosurgeons. “It has a high-frequency
pulse at the tip that shakes apart the tissue ahead
of it, but in a minute area,” he explains. “The
tissue separates before you, like the biblical parting
of the waters. You can see the blood vessels before
you get to them. That’s why brain surgeons love
it, but most pancreatic surgeons are unaware of its
utility for ‘our organ.’”
Andersen first used his excavation procedure to relieve
chronic pancreatitis. He’s since shown that it’s
also a godsend for patients like Fox. “By our
standard,” Andersen says, “the Whipple
is very safe and reasonable for bad disease of the
pancreas but it may be overkill for patients without
invasive cancers.”
Fox underwent the surgery in Baltimore last fall,
and was discharged five days later. (He stayed another
week in a local hotel in case of complications—there
were none). The 49-year-old still doesn’t know
what’s wrong with his foot—but he has developed
a mission.
“I teach residents and I’m putting up
my case for discussion,” he says. “I’m
telling them that there are two treatment paths, not
one, and that, unfortunately, they may be the only
ones who know about this.”
Mary Ann Ayd
We Can See Clearly Now
 |
 |
 |
 |
| > Tracking
the brain’s blood flow |
|
|
From the outside it may look like any other CT scanner,
but thanks to its 256-slice technology, it’s
anything but. The latest idea from Toshiba, the prototype
scanner spent several months here last spring and has
left Hopkins collaborators like Kieran Murphy, director
of interventional neuroradiology, anxiously anticipating
a permanent version, due later this year.
“This is a major breakthrough,” Murphy
says. “It’s one of the most exciting tools
I’ve ever seen in medicine.”
The only CT scanner in North America that uses 256-slice
technology, it promises to quadruple the volume of
tissue viewed in a single take—and give ER physicians
a quick and commanding glimpse into the early stages
of a stroke, many of which can be successfully reversed
with clot-busting drugs if diagnosed within the crucial
first three hours.
“We can get the imaging done in less than an
hour,” says Murphy. The quicker process also
spares patients needless exposure to radiation, he
notes.
And the 256 enhances the view into other critical
organs, like the heart and liver. Cardiologist Joao
Lima, who has headed up cardiovascular testing for
the new technology at Hopkins, says the scanner’s speed allows him
to take a much quicker shot of a beating heart—down
to two seconds or less—valuable in detecting
arrhythmias, calcium deposits or other areas of restricted
blood flow.
Ramsey Flynn
The Mini Exam with Maximal Staying Power
The most-cited paper in neuropsychiatry grew out of a husband/wife exchange.
As a third-year resident in the fall of 1973, Susan
Folstein made daily rounds of the geriatric ward at
Cornell Medical Center’s Westchester Hospital.
Husband Marshal Folstein was the ward’s attending
psychiatrist. Like the other residents, Susan was supposed
to assess the mental state of each patient and identify
any cognitive impairment. As Marshal remembers it,
she’d report, “Mrs. Jones is doing better
today, or she’s doing worse.” And he would
always reply, “But how do you know she’s
better?”
Hopkins’ legendary psychiatrist Paul McHugh,
now retired, was then the residency training director
at Cornell. “Because Susan was married to Marshal,” McHugh
jokes, “she could only put up with this for so
long.” One day, exasperated, she finally said, “Why
don’t you just write down all of the questions
you want me to ask these people?”
So that night, Folstein did. He knew from his previous
neurology training the kinds of questions to ask: simple,
direct, objective. What day is it? Spell world backwards.
Repeat the following. They targeted cognitive function
only, rather than moods or perceptions. He called his
final product—a 30-point scale based on just
11 questions—the Mini Mental State Examination
(MMSE). The test could be given in just 10 minutes.
Susan Folstein immediately began using the MMSE with
her patients, and soon the pair set up a trial to see
if the exam could differentiate among patients with
various cognitive disorders. It could. The MMSE scores
of the 206 patients in the trial reliably predicted
whether they had dementia, depression or normal cognitive
functioning (roughly any score above 24).
“We were just kids; we didn’t have any
training. We just needed it to do our work everyday,” recalls
Marshal. But the test was revolutionary. “And
once we had it,” McHugh says, “it became
obvious that nobody else had anything else like it.”
With McHugh’s help, the pair submitted their
results to the Journal of Psychiatric Research. The
paper was published in 1975, about the time that all
three authors moved to Johns Hopkins. It’s since
been cited in the scientific literature more than 19,000
times—making it the most-cited paper in neuropsychiatry.
Marshal Folstein attributes some of its popularity
to an 18,000-patient epidemiological survey of mental
health conducted by Hopkins and four other large medical
centers in the early 1980s. The survey’s designers
used the MMSE as one of the screening tests, thus validating
its effectiveness to the entire field. “And for
whatever reason, it has since become the standard test
for pretty much any drug study that involves Alzheimer’s
or dementia,” says Marshal Folstein, who, with
Susan, now serves on the faculty in the Department
of Psychiatry and Behavioral Services at Hopkins.
“Every psychiatrist in training knows what a
Mini Mental score of 24 means,” McHugh says. “They
know 24 like we all know 98.6.”
Virginia Hughes
A Gentler Fix for Broken Aortas
It’s the sort of injury that smart trauma teams
look for whenever they receive the survivors of a high-speed
car crash. Though the patients’ broken bones
might be instantly obvious, the deadliest culprit may
lurk within—a torn aorta, either actively leaking
blood into the chest or about to come apart. The complication
typically propels surgeons into an urgent open-chest
procedure that involves sawing through the ribs and
replacing the torn portion of the vessel with an artificial
graft.
But what happens when a patient is too fragile to
survive heavy surgery and further blood loss? Such
a case presented itself when 72-year-old Raymond Sheffler
was brought into the Emergency Department at Johns
Hopkins Bayview Medical Center bleeding heavily from
five cracked ribs and other injuries sustained in a
head-on collision minutes earlier. A sharp-eyed radiologist
then detected the torn aorta next to Sheffler’s
heart, accompanied by a telltale bulge in the great
vessel.
Sheffler’s age and other injuries made him a
high-risk candidate for open-chest surgery, yet his
stars had clearly aligned—Bayview’s chief
of endovascular surgery, Mahmoud Malas, is an expert
in precisely this type of injury.
Malas decided Sheffler was the perfect candidate for
a minimally invasive approach much like the one used
in common cardiac stenting procedures. The surgeon
made a 2-inch incision into the femoral artery in Sheffler’s
groin, deployed a delivery sheath into the artery to
smooth the way, and threaded it up close to the aorta’s
injury site. He then inserted a catheter through the
sheath. The tip of the catheter was equipped with a
4-inch self-expanding stent. Using intraoperative imaging
to guide placement of the endograft, Malas triggered
its expansion after it straddled the aorta’s
rupturing section.
Once the endograft was deployed, blood again flowed
securely through Sheffler’s biggest blood vessel.
Sheffler was sent home three days later. An open-chest
procedure would have easily required a weeklong hospital
stay and extensive rehab.
Malas says about 8,000 Americans suffer from ruptured
aortas annually—mostly from high-speed collisions—and
that up to 90 percent die at the scene. Of the remaining
10 percent who make it to the ED, he says, half die because
their condition isn’t recognized. He is bullish
about the endograft procedure because it’s proving
safer than open-chest techniques—and it also reduces
the risk of diminished nerve function to the limbs that
can accompany open procedures. “This procedure
only took two hours,” he says of the Sheffler case. “He
only lost 10 ounces of blood, about one-tenth of what
he would have lost in an open-chest procedure.”
Ramsey Flynn
Averting Sudden Cardiac Death
A new genetic test could offer an
early warning for dangerous arrhythmias.
In their quarter-century campaign to accurately diagnose
one of the most mysterious causes of sudden cardiac
death, scientists are closing in on their quarry with
the aid of improved genetic screening. “In many
cases,” says cardiologist Hugh Calkins, “we
can now pin it down.”
One of every 5,000 people has arrhythmogenic right
ventricular dysplasia, or ARVD. Tragically, it’s
responsible for 5 percent of sudden cardiac deaths
in young people in the United States—and is often
the culprit behind the abrupt collapse of athletes
on the playing court and field.
But the process of diagnosing ARVD has always been
vexing, says Calkins, who has been immersed in the
chase for eight years and now heads a team of 10 specialists
at Hopkins. ARVD’s presence too often becomes
clear only after an autopsy reveals telltale signs
of the condition, such as a severely dilated right
ventricle whose walls are thinned and replaced with
fibro-fatty tissue.
While a family history of ARVD is obviously a strong
indicator (a third of an afflicted person’s children
will get it), Calkins, who serves on a task force charged
with revising the condition’s diagnostic criteria,
says one genetic mutation has recently come to the
fore—in a protein known as plakophilin-2. This
PKP2 error is associated with up to 45 percent of ARVD
patients.
What’s more, Calkins adds, is that patients
with PKP2 are also more likely to develop ARVD at an
early age, which hints at the condition’s disproportionate
toll on young athletes.
If ARVD can be caught in advance—PKP2 can be
detected through a blood test with genetic screening—patients
can be advised against strenuous activity and their
arrhythmias can be temporarily relieved with ablation
therapy. The more optimal long-term solution: implantation
of a defibrillator, which can detect and correct dangerous
arrhythmias whenever they strike.
Calkins hopes the revised criteria for ARVD will be published
in early 2008.
Ramsey Flynn
|