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Straight
Track #24
Best Tests & Care For Prostate Cancer
Consumer Reports on Health
August 2000
Vol. 12, No. 8
With the graying of the work force in the railroad
industry, prostate cancer has become a major concern of railroaders' and
their families. Consumer
Reports' recently published "Best Tests and Care for
Prostate Cancer" is the subject matter of this edition of Straight Track.
Foreword by J. Dillon Hoey, Hoey & Farina
hoey@felahfd.com / (888) 425-1212
New York City Mayor Rudolph Giuliani doesn't usually
waffle on the issues. But
when he was diagnosed with prostate cancer this spring he reportedly spent
more than a month pondering the best treatment for his condition. Surgery? Radiation?
Or waiting it out?
Experts disagree on the best treatment for this
malignancy that kills more men each year than any other tumor except lung
cancer. They even disagree on
the role of early detection. The
U.S. Preventive Services Task Force, an influential government panel,
recommends against routine testing for prostate cancer, arguing that
treatment may be worse than the disease.
The American Cancer Society and the American
Urological Association disagree. So
do Consumers Union's medical consultants.
But deciding whether to test for the disease is a complex issue,
and choosing the right therapy is difficult.
Here's what you need to know to help you sort through those often
painful choices.
TO TEST OR NOT
TO TEST
The prostate-cancer blood test measures the level of
a protein called prostate-specific antigen (PSA), which is usually higher
than normal when the prostate gland is enlarged, inflamed, or cancerous.
The government task force and a number of physicians have raised
two major objections to using the PSA test to screen men for prostate
cancer. First, studies show
that anywhere from 30 to 60 percent of men eventually develop prostate
cancer. But the malignancy
often grows so slowly that it smolders harmlessly within the prostate for
decades. Some researchers and
physicians worry that the test may detect many of those un-aggressive
tumors and thus lead to an avalanche of needless surgery and radiation
therapy. Second, critics have long maintained that there is no good
evidence that early detection of prostate cancer actually saves lives.
But recent evidence has undercut both of those
arguments and strengthened the case for PSA testing.
First, several studies have carefully analyzed thousands of
prostates that were surgically removed because of an elevated PSA level
followed by a biopsy that confirmed the cancer.
The studies show that 75 to 95 percent of those cancers posed a
substantial risk of turning deadly within an estimated average of 15
years; many of them would have turned deadly within 5 to 10 years.
Second, growing evidence strongly suggests that PSA
screening is saving lives, by allowing doctors to catch the aggressive
cancers early. From 1991 (the
latest year analyzed), the number of prostate-cancer deaths in the U.S.
fell by 16 percent, the first decline in decades.
That occurred despite a sharp increase in the number of prostate
cancers detected during that period.
An Austrian study, presented in April at the annual
American Urological Association meeting, provides stronger evidence.
From 1993 to 1998, the prostate-cancer death rate dropped by 42
percent in Tyrol, the only Austrian state where PSA screening is free and
where most men get tested; in the rest of the country, prostate-cancer
mortality had held steady.
Recommendation:
Our medical consultants say the available evidence is sufficiently
strong to justify annual PSA testing for all men over age 50 who can
reasonably expect to live more than ten years.
Younger high-risk individuals high-risks individuals - including
men who are African-American, or, like Mayor Giuliani, have a father or
brother who had the disease - should start getting screened at age 40.
In addition, all PSA testing should be accompanied by
a digital rectal exam, in which the doctor evaluates the gland by
inserting a gloved finger into the rectum.
The digital exam can help detect not only rectal cancer but also
some of the prostate cancers missed by the standard PSA test.
HOW TO TEST
Some of the PSA in the blood is bound to other
proteins; the rest floats freely. In
the standard PSA test, physicians consider only the total amount of
circulating PSA. The usual
minimum PSA score that warrants a biopsy is 4.0 nanograms per milliliter.
If the PSA level rises 1.5 points or more during a two-year period,
consider biopsy, even if the total score is below that threshold.
The standard approach not only misses some cancers
but can also raise false alarms; in fact, only about 25 percent of
elevated total-PSA scores are actually caused by cancer.
IN other cases, the elevation is due to benign enlargement, a very
common condition in older men, or to inflammation of the gland due to
infection. Each of those
false alarms necessitates a mildly uncomfortable, expensive biopsy - about
$500 to 800, on average - to rule out cancer.
(You may want to ask your doctor to apply lidocaine, a topical
anesthetic, before the biopsy.)
To increase the test's accuracy, doctors have
modified the analysis of PSA scores by considering either the man's age or
the individuals components of the total PSA score.
Here's what our medical consultants say about those changes:
Younger age,
lower PSA.
Studies show
that lowering the threshold for under going biopsy from the usual 4.0
nanograms per milliliter to 2.5 in high-risk men under age 50 leads to
only about 5 percent more biopsies, but identifies about 20 percent more
cancers. In addition, using a
threshold of 3.5 for men in their 50s probably has similar benefits.
Note that some physicians now employ the opposite
approach: higher thresholds
for men over age 60. While
that strategy cuts down on the false alarms, it increases the number of
missed cancers by a roughly equal amount.
Recommendation:
The best strategy for improving the accuracy of the PSA test is to
use lower threshold values for men in their 40s and 50s.
Raising the threshold for older men is not advisable.
Free PSA. Men with prostate cancer tend to have a smaller percentage of free
PSA than other men have. SO when the total PSA score is minimally elevated, some
doctors now consider the ratio of free to total PSA; they recommend biopsy
only when that ratio is less than 25 percent.
That cuts back on the number of unnecessary biopsies by about 20
percent, while missing only about 5 percent more cancers.
And some evidence suggests that the missed cancers are usually the
least aggressive ones.
Recommendation:
Men who are willing to tolerate a slightly increased chance of
missing a cancer in order to gain a much greater chance of avoiding a
needless biopsy may want to consider using the free-to-total PSA ratio,
particularly when the total PSA is only slightly elevated for a man's age.
But the safer, and thus generally preferable, route is to rely on
the total score, not the ratio. (The
free-PSA test is helpful to clarify the results when a biopsy fails to
find any cancer even thought the total PSA score is elevated.
I that case, it's possible that the biopsy simply missed the
cancer. A low free-to-total
ratio may then warrant repeating the biopsy, while a higher ratio would
tend to bolster the negative result.)
Testing dos
and don'ts:
All men
should take these steps before having their PSA measured to help ensure an
accurate result:
·
Don't ejaculate for two days before the test, since that can
raise PSA levels.
·
Have your blood drawn before, not after, the rectal exam,
which may also raise the PSA level.
·
Remind your doctor if you're taking finasteride (Propecia, Proscar), which can lower the total PSA level (but not the
free-PSA
level). Also tell your doctor if you're taking the herbal formula PC-SPES
or large doses of the antioxidant lycopene, since they may also lower the
PSA level. (Studies have
recently shown that the herbal remedy saw palmetto, often used to treat
prostate enlargement, does not affect the PSA - though you should still
inform your doctor if you're taking the supplement.)
·
Have your PSA measured at the same laboratory, using the
same method, each year.
·
If the PSA reading indicates a borderline elevation or a
significant increase since the previous reading, repeat the test in three
or four months. If the
initial reading indicates a clear-cut elevation, repeat the test
immediately, to confirm that finding.
You may want to ask your physician about prescribing antibiotics
before repeating the test, to rule out possible prostate inflammation.
SURGERY OR
RADIATION
If the biopsy confirms cancer, the first step is to
determine the odds that the malignancy is confined to the gland and thus
potentially curable - as it is in some 70 to 85 percent of cases.
To predict whether the cancer has spread, your physician should use
a formula that combines three factors:
the PSA level, the results of the rectal exam, and the
"Gleason score," which measures the aggressiveness of the cancer
cells.
When the formula indicates that a tumor is probably
still localized, surgery to remove the entire gland has a ten-year cure
rate of 70 to 90 percent. (In
the remaining 10 to 30 percent, either the formula was wrong or the
surgeon failed to remove all of the gland.)
That success rate is at least as high as any other prostate
treatment's. The available evidence, while limited, does suggest that
surgery is probably more effective than other treatments as preventing
cancer recurrence beyond ten years.
Surgery poses certain risks, however, notably
permanent urinary incontinence in an average of about 10 percent of cases
and impotence in about 60 percent. But
the impotence rate is often lower when a highly skilled surgeon performs a
version of the operation designed to spare the nerves required for an
erection, without jeopardizing chances for a cure.
Even when surgery does cause lasting impotence, the condition can
usually be treated successfully with sildenafil (Viagra) if enough nerves
were spared. (Sildenafil also
effectively treats impotence caused by radiation therapy.)
Moreover, the rates of sexual and urinary complication from other
prostate-cancer treatments are nearly as high as those from surgery, and
the rate of fecal incontinence may be even higher.
Recommendation:
Surgery provides the best
chance of a permanent cure and has risks comparable to those of other
therapies. It's the best
option for most men whose prostate cancer appears to be confined to the
gland and who can expect to live more than ten years or so if the cancer
is cured.
You can increase your chance of a surgical cure and
reduce your risk of complications by finding a skilled surgeon.
Look for someone who:
·
Is certified by the American Board of Urology.
·
Performs nerve-sparing surgery.
·
Performs the operation several times per week.
·
Says his or her surgical complication rates are below 60
percent for impotence and 10 percent for incontinence.
However, surgery is
not appropriate for some men, notably those who are sufficiently weakened
by sickness or advanced age - in general, over 70 or so - that the normal,
generally small risks of surgery and general anesthesia rise sharply. Illness and age can also slow recovery from surgery.
The following is a rundown on the three most common alternatives:
External beam
radiation.
Several
studies lasting up to ten years suggest that standard radiation therapy,
which is designed to destroy the prostate gland, prevents recurrence about
as effectively as surgery does. But
since radiation doesn't eliminate the entire gland as reliably as surgery
can, it's possible that the malignancy will re-emerge after a decade or
more. Beam radiation treatment lasts seven weeks, five days a week,
for about two to three minutes. This
type of treatment causes permanent impotence and urinary incontinence
about as often as surgery does, and It's more likely to cause fecal
incontinence as well s temporary rectal bleeding.
But again, the success rates may be higher and the complication
rates lower when the beams are administered by a skilled radiation
oncologist.
Recommendation:
Because radiation is less traumatic than surgery and has roughly
comparable ten-year success rates, it's usually the preferred treatment
for men whose life expectancy is less than a decade because of other
health concerns. If you
decide to undergo beam radiation, look for a radiologist who:
·
Is certified by the American Board of Radiology.
·
Practices at a medical center that uses a precise targeting
technique called three-dimensional conformal therapy, and has treated at
least 20 patients with that technique.
·
Says his or her complication rates are lower than the
above-mentioned averages for surgery.
Brachytherapy.
In this procedure radiologists implant dozens of radioactive
"seeds" directly in the prostate, using hollow needles inserted
into the gland through the perinuem, the area between the anus and the
scrotum. A growing number of
doctors and patients are now choosing brachytherapy, since it's less
traumatic than surgery and requires only one day in the hospital, compared
with three days for surgery and seven weeks of treatment for beam
radiation. Moreover, a few
studies published several years ago suggested that the procedure was
almost as effective as surgery, with much lower complication rates.
However, recent studies have raised doubts on both accounts.
A Harvard study found that men with moderately or
highly aggressive cancers who receive the radioactive seeds are about
three times as likely to have a relapse within five years as those who
undergo either surgery or beam radiation.
Another study, from Seattle, involving men with less-aggressive
tumors, found a ten-year recurrence rate of about 40 percent after seed
therapy, roughly double the rates for surgery or beam radiation.
In addition, recent reports indicate that the risks
of impotence and urinary incontinence are nearly as high for the seeds as
for the other two treatments. And
seeds, like beam radiation, appear to pose a greater risk of fecal
incontinence. Indeed, a
recent study from the University of California at Los Angeles that
compared the overall quality of life 18 months after surgery or seeds
found no difference between the two.
Because of those problems, some radiologists now combine seeds with
beam radiation. But there's
little evidence that the combination works any more effectively than beam
radiation alone, and it's more likely to cause side effects.
Recommendation:
This procedure appears to make sense only for men whose overall
health or advanced age precludes both surgery and standard radiation
therapy. However, those men
may be served just as well by watchful waiting (see below).
If you do opt to receive the seeds, look for someone who is
certified by the American Board of Radiology and who has performed at
least 25 procedures.
Watchful
waiting. Physicians can
now use the PSA level, biopsy results, and rectal examination to help
predict which tumors are least likely to ever spread beyond the gland, and
thus which patients might be appropriate candidates for watchful waiting,
or simply monitoring the disease and trying to control it if it spreads.
For example, one study that followed some 770 mean who chose to
forgo treatment found that those with the least aggressive tumors faced
less than a 10 percent risk of dying of cancer in the next 15 years.
In comparison, men who had more aggressive tumors faced a 20 to 90
percent risk.
Recommendation.
Watchful waiting is a reasonable choice mainly for men whose health
or age makes it unlikely that they will live longer than five or ten
years, especially when they have low PSA and Gleason scores (under 10 and
5, respectively) and the rectal examination does not detect any palpable
tumor.
Treating
advanced cancer:
Aggressive options when the tumor
has spread
When the
combination of your PSA level, digital exam, and biopsy results
suggest that the cancer has probably escaped the prostate gland, doctors
will try to assess how far the malignancy has spread.
That usually involved performing a bone scan and possibly a
magnetic resonance imaging (MRI) or computerized tomography (CT scan of
the abdomen and pelvis. (Some
urologists order a bone scan even on patients who almost certainly have
localized cancer, to rule out the slight chance of spread to the bones, as
well as to provide a baseline image of the bones to monitor the progress
of the disease.)
If those imaging tests fail to detect any spread,
it's still possible that the cancer is confined to the gland. It's also possible that the disease may have spread only to
an adjacent region: the
capsule that surrounds the prostate, the tiny seminal-fluid-producing
glands adjacent to the prostate, or the nearby lymph nodes.
In those cases, cure is still possible, though much less so than
when the cancer remains confined to the gland itself.
A STEPPED-UP
ATTACH
The best treatment in such cases is even more
controversial than for localized cancer.
But CU's medical consultants say that the same general guidelines -
surgery for younger men, beam radiation for older men - still usually
apply. Some doctors recommend
taking an especially aggressive approach to these potentially curable
cancers by adding other treatments to the surgery or radiation:
chemotherapy, testosterone-blocking drugs (since that male hormone
fuels the growth of prostate cancer wherever it spreads), or radiation (to
supplement surgery).
When the malignancy has already reached the bones or
other organs, doctors focus on attaching the testosterone levels.
One option is "medical castration" via periodic
injections of a drug that blocks testosterone production.
The alternative is actual removal of the testicles, which produce
most of the hormone.
Antihormone treatment causes loss of sex drive,
impotence, and other changes such as tenderness and enlargement of the
breasts and even hot flashes. But
it can ease cancer symptoms and may prolong life by a few months to
several years.
UNCONVENTIONAL
APPROACHES
Many men with prostate cancer augment their treatment
with alternative therapies, especially herbs and megavitamins.
A few small studies in men with cancer do suggest that an herbal
formula called PC-SPES, a combination of several Chinese herbs, as well as
high doses of the antioxidant lycopene, may lower PSA levels.
That might indicate that they're fighting cancer.
However, that effect is far from proven.
If you do take PC-SPES, lycopene, or any other alternative
treatment, tell your doctor. Those
agents often have side effects. For
example, PC-SPES may produce some of the same side effects as
anti-testosterone therapy, as well as potentially dangerous blood clots.
Moreover, since doctors monitor the effectiveness of
prostate-cancer treatment in part by tracking PSA levels, they need to
know about anything you take that might influence PSA levels.
Summing
Up
Since the advent of PSA screening a decade ago, the
mortality rate from prostate cancer has dropped, strongly suggesting that
the early diagnosis and aggressive treatment of localized prostate cancer
saves lives.
Men who can expect to live longer than a decade
should generally have their PSA level measured annually, starting at age
50; high-risk individuals, African-Americans and any man whose father or
brother had the disease- should start testing at age 40.
Talk to your doctor about lowering the threshold for worrisome
scores from traditional 4.0 to 2.5 if you're in your 40's and to 3.5 if
you're in your 50's.
If it's likely or even possible that the cancer is
confined to the glad, surgery is usually the treatment of choice for men
who can expect to live more than ten years.
Finding a skilled surgeon who performs nerve-sparing surgery can
increase the chance of cure and decrease the risk of incontinence and
impotence. If impotence does
occur, Sildenafil (Viagra) may restore potency, particularly after the
nerve-sparing operation. (Sildenafil
often helps after beam radiation, too.)
External-beam radiation is usually the best choice
for men who have a life expectancy of no more than a decade. Look for a radiologist who performs three-dimensional
conformal therapy and has the favorable complication rates described
above. Radioactive seeds are
generally not a good choice, since on average they're almost as likely to
cause complications and much less likely to cure the cancer.
Watchful waiting is a reasonable option for men with a life
expectancy under five to ten years whose PSA levels, biopsy results, and
rectal exam suggest they have a particularly slow growing tumor.
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