Prostate Cancer: No One Answer for Testing or Testament
by John Henkel
Russ Ingram didn't sense pending calamity when he
reported for a company physical seven years ago. After all, he was in good
shape and, at 39, still very much a robust young man with no signs of
health problems.
During part of the exam, however, the doctor noticed
that Ingram's prostate was enlarged. While this can indicate a tumor,
often it signals a common benign prostate condition, usually in men much
older than Ingram. But a visit to a urologist produced the grim news that
his condition was not benign. He had prostate cancer.
"I was devastated," says Ingram. "Due
to my age, I didn't think there was anything to worry about. It caught me
totally off guard. I didn't even know where the prostate was."
To be sure, Ingram's case is not typical. His age at
diagnosis placed him well outside the primary risk group for prostate
cancer. Statistically, at least 80 percent of prostate cancers occur in
men over 65. In fact, men in their 30s are not usually tested for prostate
cancer in a physical and Ingram says it was just "a fluke" that
the doctor discovered the enlarged prostate.
While the disease can strike any man, younger men at
increased risk include African Americans, who have double the risk and
death rate of white men and often are stricken before age 50. Men with a
family link to prostate cancer through brothers or fathers also are at a
greater risk of getting the disease before 50.
The American Cancer Society estimates that in the
year 2000, nearly 180,400 American men will be diagnosed with prostate
cancer and 31,900 will die from the disease. (In comparison, 1998
estimates for lung cancer in men are 171,500 cases and 160,100 deaths; for
colorectal cancer, the estimates are 131,600 cases and 56,000 deaths.)
Despite the bleak numbers, 89 percent of men diagnosed with the disease
will survive at least five years and 63 percent will survive at least 10
years, the society says. These rates are partly due to improved screening
tests and diagnostics the Food and Drug Administration has approved that
discover cancer in early stages. Also, prostate cancer is very
slow-growing in some men, who may die of some other cause before the
disease takes its toll.
Detecting Prostate Cancer
The prostate is a male sex gland, about the size of
a walnut. It produces a thick fluid that helps propel sperm through the
urethra and out of the penis during sex. Because the prostate is just
below the bladder and directly in front of the rectum, a doctor can check
the size and condition of the gland by inserting a rubber-gloved finger
into the rectum. This digital rectal exam (DRE) has for years been the
gold standard for detecting prostate cancer as well as the noncancerous
disorder benign prostatic hyperplasia
In 1985, FDA approved the first test for monitoring
blood levels of a substance called prostate specific antigen (PSA), which,
when elevated, can indicate cancer presence. Several companies now have
approved PSA tests, which, experts say, have revolutionized the screening
and monitoring of patients.
PSA is an ideal marker for prostate cancer because
it is basically restricted to prostate cells. A healthy prostate will
produce a stable amount--typically below 4 nanograms per milliliter, or a
PSA reading of "4" or less--whereas cancer cells produce
escalating amounts that correspond with the severity of the cancer. A
level between 4 and 10 may raise a doctor's suspicion that a patient has
prostate cancer, while amounts above 50 may show that the tumor has spread
elsewhere in the body.
Most PSA tests measure "total PSA," or the
amount that is bound to blood proteins. In 1998, FDA approved the Tandem R
test, which measures not only total PSA but another component called
"free PSA," which floats unbound in the blood. Comparing the two
helps doctors rule out cancer in men whose PSA is mildly elevated from
other causes. A 1995 study in the Journal of the American Medical
Association showed that the free PSA test can reduce unnecessary prostate
biopsies by 20 percent in patients with a PSA between 4 and 10.
The availability of increasingly sensitive testing
devices has created a debate over when men should be tested for prostate
cancer, how often, and whether men under 50 with no symptoms should be
routinely screened. Opponents say mass screening would be expensive, and
the verdict is still out on whether early detection can curb the disease's
mortality rate. But proponents say early detection is the closest thing
currently to a cure and that it can save lives. The American Cancer
Society and the American Urological Association recommend annual PSA
tests--along with the digital exam--for all men over 50 and for high-risk
men over 40.
The PSA test, though a powerful tool, "is not
perfect," says Jean Fourcroy, M.D., a urologist and medical officer
in FDA's Center for Devices and Radiological Health. Besides being thrown
off by noncancerous conditions, the tests can vary between manufacturers.
"Patients and physicians should use the same brand of PSA test
throughout monitoring because of these possible variations," Fourcroy
says.
When PSA or digital tests indicate a strong
likelihood that cancer is present, doctors usually order a transrectal
ultrasound (TRUS), a probe inserted into the rectum that uses sound waves
to "map" the prostate and show any suspicious areas. Doctors
then may take biopsies of various sectors of the prostate using tiny
hollow needles inserted through the rectum. Biopsies are the only
definitive way to determine if prostate cancer is present.
If the biopsy indicates cancer, the doctor then
"stages" the tumor based on which biopsy specimens contain
cancer, the extent of cancer, and the location of cancer in the specimens.
Staging also depends on the extent and location of cancer outside the
confines of the prostate.
Another important measure, the Gleason score, gauges
the probable aggressiveness of the tumor based on the cellular differences
of the cancer. Tumor cells that look similar to normal cells tend to be
less aggressive, while those distributed randomly with uneven edges are
likely to spread rapidly. Two numbers, each from 1 to 5, are assigned. The
higher the numbers when the two are added, the more aggressive the tumor
is likely to be.
Doctors also examine the ploidy, or number of sets
of chromosomes in a cancer cell. Diploid cells, for example, have a
complete set of normally paired chromosomes, and tend to grow slowly and
respond well to therapy.
Recently, some doctors have begun using Partin
Tables, a scoring method developed at Johns Hopkins University that uses
PSA, Gleason number, and staging to predict if the disease is confined or
has spread to other sites. Doctors also can determine cancer spread with
imaging techniques such as bone scans and computerized tomography (CT)
scans.
Treating the Disease
Armed with diagnostic data, patients and their
doctors must then decide on a treatment course. It is at this point that
patients must be well educated, says FDA's Fourcroy. "The decisions
made [on treatment] are so crucial and will have such an effect on quality
of life, men must weigh them very carefully," she says. "And
they must also remember to include their partners in the decisions because
they will be affected by the course of action too."
One possible treatment is actually no treatment at
all. Doctors call it watchful waiting, and it is best
suited for men with a 10-year life expectancy or less who have a low
Gleason number and whose tumor has not spread beyond the prostate. The
idea is that in these men the cancer is growing so slowly, they likely
won't die from it. More radical treatments such as surgery might be more
dangerous than simply waiting. Marty Feins, 77, opted for watchful waiting
in 1993 when diagnosed with prostate cancer, and he's "going
great," he says. Though the Las Vegas man was deemed a good candidate
for radiation treatment, he says he did a lot of research and decided his
was a prudent course. His PSA level is elevated but is not rising rapidly.
"Right now I'm holding steady," he says. "In fact, if I
hadn't had a biopsy, I wouldn't even know I have [cancer]."
Californian Jerry Coleman, 61, diagnosed in 1995,
opted for a surgical treatment called radical prostatectomy (RP),
in which the prostate is completely removed. If performed when cancer is
confined to the gland, RP is tantamount to a cure since in theory it
removes all the cancer. Coleman says he chose RP because he was unsure of
the track record of other treatments. "I felt comfortable that this
was the appropriate attack considering my health, age, and the stage of my
disease," he says.
Besides being a serious operation that requires
weeks of recuperation, RP can have lingering side effects, including
impotence and incontinence. Until the early 1990s, virtually all RP
patients were saddled with these effects. But "nerve sparing"
techniques developed at Johns Hopkins University have preserved urinary
and erectile functions in increasing numbers of RP patients. The CaverMap,
a device cleared by FDA in 1998, aids surgeons in locating nerve bundles
to help avoid severing nerves related to continence and erections when
removing the prostate.
Radiation is a treatment option
that may be less traumatic than RP and appears to have similar results
when used in early-stage patients. Radiation also produces side effects,
including impotence, in about half of patients. It can be applied through
an external beam that directs the dose to the prostate from outside the
body. FDA also has cleared low-dose radioactive "seeds," each
about the size of a grain of rice, that are implanted within the prostate
to kill cancer cells locally. Called brachytherapy, the seeding technique
is sometimes combined with external-beam radiation for a "one-two
punch." Studies done at the Georgia Center for Prostate Cancer
Research and Treatment show that 68 percent of men treated with both
radiation methods applied simultaneously are cancer free 10 years after
treatment. Intel Corporation chairman Andy Grove, who was Time magazine's
1997 "Man of the Year," underwent the combined radiation therapy
in 1995. According to company spokesman Howard High, Grove, 62, is
"in excellent condition" now.
Cryotherapy, in which prostate
tumors are killed by freezing, shows encouraging early results. But some
medical professionals consider it experimental with not enough long-term
data yet to determine its effectiveness.
Hormonal therapy is often used in
all phases of prostate cancer treatment to help block production or action
of the male hormones that have been shown to fuel prostate cancer. Among
widely used approved hormone blockers, often used in combination, are
Lupron (leuprolide acetate), Casodex (bicalutamide), Eulexin (flutamide),
Nilandron (nilutamide), Zoladex (goserelin acetate implant), and Viadur
(leuprolide acetate). Because the testicles produce male hormones, some
men also undergo testicle removal to cut off the hormone supply. Advanced
prostate cancer patients are usually treated with any number of
chemotherapeutic drugs such as Novantrone (mitoxantrone), which do not
cure the disease but often do ease pain and other symptoms.
Looking Ahead
Incidences of prostate cancer have dipped slightly
in the last five years, says the American Cancer Society. But as FDA's
Fourcroy says, there's no "magic bullet" right now that will
significantly reduce prostate cancer cases or deaths. As for the future,
some strong possibilities exist.
- Over a hundred drugs and vaccines for treating
prostate cancer are currently in clinical trials. Proposed drugs that
may choke off the blood supply to prostate tumors, along with vaccines
that rev up the immune system to attack prostate tumors, appear
possible.
- Treatments based on the hormone IGF-1, which can
be a marker for increased prostate cancer risk, are feasible,
researchers from McGill and Harvard Universities report.
- Studies examining the relationship between diet
and prostate cancer have identified a high-fat diet as a risk factor
for the disease. Other diet research has shown a possible inhibitory
effect for prostate cancer when foods such as soy products and cooked
tomatoes are added to the diet.
- A study sponsored in part by the National Cancer
Institute showed that vitamin E may reduce prostate cancer risk by 30
percent, but NCI stopped short of recommending supplements.
- NCI is studying 18,000 men over seven years to
determine if the drug Proscar (finasteride) can prevent prostate
cancer.
Meanwhile, patients are benefiting from prostate
cancer's increasing visibility. "It's finally coming out of the
closet," says Howard Waage, 51, a California prostate cancer patient.
"It's crucial for us men to be on top of our health, and that's
easier to do now than ever."
Out in the Open
Until this decade, not much support or information
was available for prostate cancer patients. Then, in the early 1990s,
public figures began talking openly about the disease, books and articles
appeared, and hundreds of support groups sprang up nationwide. Numerous
celebrity deaths from prostate cancer--among them actor Telly Savalas,
musician Frank Zappa, and Nobel Prize winner Linus Pauling--were clustered
a few months apart. Other personalities, including former Sen. Bob Dole,
golfer Arnold Palmer, and retired Gen. H. Norman Schwarzkopf, went public
with their experiences. Men started getting the message that the disease
can strike any man and that it is possible to survive prostate cancer if
it is discovered early enough.
Along with the abundance now of printed prostate
materials, the burgeoning popularity of the Internet has helped spawn a
new breed of prostate cancer patient, a well-informed man who is in charge
of his destiny. Huge amounts of reliable material from organizations such
as the American Cancer Society, the National Cancer Institute, and various
university hospitals are available online.
Patients also are using the Internet to connect with
fellow patients through electronic mailing lists. This allows them to
compare notes and get feedback on treatment decisions. Many prostate
cancer doctors post messages to mailing lists and answer patient
questions.
"I'm not sure I'd be alive today if it weren't
for information I've gotten on the Internet," says prostate cancer
patient Russ Ingram, who has located experts online who have helped him
select the latest treatments for his spreading cancer.
Noncancerous Prostate Disorders
Up to 90 percent of men over age 80 have some
symptoms of the condition known as benign prostatic hyperplasia (BPH).
Half of men over 50 have it.
BPH is not cancer, but it can display similar
symptoms: prostate specific antigen (PSA) levels may be elevated, and the
prostate gland itself is enlarged. The condition is rarely dangerous, but
it can be aggravating for men because of the prostate's proximity to the
urethra, which runs through the gland. When the prostate becomes enlarged,
it chokes off the flow of urine, and strain may be necessary to start the
flow. Men may have frequent urges to urinate, especially at night, or they
may have a lingering sensation that the bladder isn't empty.
Treatment options include:
Heat treatments--These are
minimally invasive and generate heat within the prostate by microwave,
radio-frequency (RF), or laser energy. FDA approved the first microwave
device, the Prostatron, in 1996, and since has approved the Targis and
Urowave systems. Transurethral Needle Ablation (TUNA) was cleared in 1996
and uses RF needles inserted into the prostate to heat the tissue. FDA has
cleared three types of lasers for treating BPH: a side-firing device that
delivers laser energy from a fiber in the urethra; contact systems, which
come in direct contact with the prostate; and the interstitial laser,
which heats the prostate from probes placed within the gland.
Surgery--Transurethral resection of
the prostate (TURP) removes excess prostate tissue with special
instruments inserted into the urethra. For smaller prostates, the less
invasive transurethral incision of the prostate (TUIP) involves one or two
cuts made in the gland.
Stents--In 1997, FDA approved the
Urolume, a tube to hold open the urethra and relieve obstruction due to
BPH.
Alpha blockers--These oral drugs
relax the prostate muscles, easing pressure on the urethra. FDA has approved
Hytrin (terazosin), Cardura (doxazosin), and Flomax (tamsulosin hydrochloride).
Proscar (finasteride)--This drug
shrinks the prostate by reducing the body's conversion of testosterone to
the hormone DHT. FDA approved Proscar in 1992, and in 1998 allowed the
drug to be labeled as the first medication to reduce the need for prostate
surgery and to lower the risk of developing acute urinary retention, a
serious and painful complication of BPH. Proscar also is being tested as a
prostate cancer preventive in a massive clinical trial sponsored by the
National Cancer Institute.
Another noncancerous condition, prostatitis, can be
a bacterial infection of the prostate occurring in men of any age. Doctors
typically prescribe antibiotics for the condition, which may occur only
once (acute prostatitis) or several times (chronic prostatitis). Sometimes
the condition clears up on its own, but men should always seek treatment,
say health professionals.
John Henkel is a staff writer for FDA Consumer. This article originally appeared in the FDA Consumer magazine, published by the U.S. Food and Drug Administration, in the September-October 1998 issue.
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