More than 20 years after prostate specific
antigen (PSA) screening
for detecting prostate cancer was
introduced, physicians are working
to refine its use as a diagnostic tool.
According to Gerald Andriole, MD,
urologist at the Siteman Cancer
Center at Barnes-Jewish Hospital
and Washington University School of
Medicine, a “risk-adjusted screening”
approach to PSA testing may be of the
greatest benefit to men overall.
“Risk-adjusted screening means
making sure men at the highest risk
for developing prostate cancer receive
regular PSA tests. For the rest of men—
the majority—it means getting a
baseline PSA test around the age of 45
and then getting screenings every five
to 10 years thereafter, according to the
rate at which their PSA rises,” explains
Andriole, who also is the R.K. Royce Distinguished Professor and chief of
urology at Washington University.
Those at highest risk for prostate
cancer are African-American men;
men with two or more first-degree
relatives with the disease, particularly
if they were diagnosed at age 60
or younger; and men in their 40s
who have high PSA scores. “Rates of
prostate cancer in African-American
men are twice as high as those in
other American men, as is their death
rate from the disease,” says Siteman
urologist Arnold Bullock, MD. “These
facts make it imperative for African-
American men to get their first PSA
test between ages 40 and 45. If those
results are within acceptable ranges,
then at age 50 they should begin
getting PSA screenings annually.
Men in the other high-risk categories
should consider following the same
course of screening.”
Over Diagnosis, Over Treatment
Although annual PSA screening
is not harmful, the actions a man
may take after receiving test results
that indicate high PSA levels
sometimes are.
“It can be a slippery slope that begins
when a man learns he has an elevated
PSA. For some, that leads to having
a biopsy because they worry about
having cancer. If the biopsy does show
cancer, there may be a reaction from
the patient or his family—particularly
in the United States—to do something
immediately,” says Andriole. “That
‘something’ often means surgery or
radiation treatment, which can result
in serious adverse side effects like
impotence and incontinence.”
This chain of events is proving to be
unnecessary for a lot of men with
prostate cancer. Andriole cites the
findings of the National Cancer
Institute’s Prostate, Lung, Colorectal
and Ovarian (PLCO) Cancer Screening
Trial, in which 76,000 men have been
followed for 10 years or longer.
“The study’s data confirm that for most
men it is not necessary to be screened
annually for prostate cancer since the
large majority of the cancers we found
are slow-growing tumors that are
unlikely to result in death,” says
Andriole, who serves as the chairman
of PLCO’s prostate committee. “For
that reason, we need to modify our
current practices and stop screening
elderly men and those with a limited
life expectancy. Instead, we need to
take this targeted approach and selectively
screen those who are most likely
to benefit—young, healthy men and
those with a high risk for the disease.”
Active Surveillance
For men diagnosed with prostate
cancer, an alternative treatment
approach is active surveillance. An
increasing number of men are taking
this option when a biopsy shows
a small amount of cancer in the
prostate and microscopic examination
indicates it has a low chance of
growing aggressively.
“Studies are showing that 60 to 70
percent of prostate cancers can be
treated in this way because of the
slow-growing nature of the tumors,”
says Andriole. “For these patients,
we repeat PSA testing every three
to six months. If there is no change
or it rises only slowly, we do another
biopsy in a year’s time. If the cancer
has worsened, then we can begin
discussing treatment options.”
James “Terry” Gates, 75, a retired
college professor, is one of Andriole’s
patients who chose active surveillance.
Gates was diagnosed with prostate
cancer about two years ago. “I knew
I didn’t want aggressive, invasive
treatment if I could avoid it. The low
level of discovery in regard to the
cancer convinced me to simply get a
PSA screening every six months or so.
My PSA score has remained at about
the same level,” says Gates. “I have
confidence in my doctors, and I’m 75.
My attitude might be different if
I was 30 years younger, but at this
stage of my life, this was a realistic
choice for me.”
Diagnostic Options
Several advanced technologies
aid in the diagnosis and treatment
of prostate cancer. One of these,
TargetScan, a three-dimensional
ultrasound, helps to calculate the
size and shape of the prostate and to
define the location of the cancer.
Its accuracy allows urologists to
perform follow-up biopsies in
the exact area where cancer was
previously detected, thus providing a
more exact assessment of the cancer’s
progression. It also aids in radiation
therapy and in an investigational
treatment called focal ablation, which
uses freezing to destroy tumor tissue.
High-strength magnetic resonance
imaging (MRI) with a 3 Tesla (3T)
magnet, which can show the location
and size of prostate cancers, is another
available tool. The information it
provides helps determine whether
active surveillance is a viable option.
Treatments
“Both TargetScan and 3T MRI can
help us with focal ablation of small
cancers,” says Andriole. “Since we
know the precise location of the tumor
from the TargetScan and/or MRI, we
can insert a needle into that region of
the prostate and destroy it. Treating
the cancer in this way increases
patients’ odds that they will remain on
active surveillance without the need
for other, more aggressive treatment
in the future. This ‘micro-invasive’
approach to prostate cancer is apt
to become more widespread in the
Often, men choose intensitymodulated
therapy, which targets
higher doses of radiation to the
prostate and less to surrounding
organs. Others opt for brachytherapy,
in which radioactive seeds are
implanted into the prostate to kill
cancer cells. These treatment methods
also employ either TargetScan or 3T
MRI to assist with precise targeting
of the radiation.
“There is no one treatment that is
right for every man,” says Siteman
radiation oncologist Jeff Michalski,
MD, vice chairman for radiation
oncology at Washington University
School of Medicine. “I often tell my
patients that what worked for their
neighbor or their best friend may not
be the best treatment for them. That’s
why men who undergo treatment for
prostate cancer need to understand
the risks and benefits of surgery and
radiation therapy.”
Michalski adds, “Patients should
choose a radiation oncologist or
surgeon who specializes in treating
prostate cancer. Their outcomes
generally are better, and patients
have fewer complications during
treatment and after.”
What the Future Holds
In an ideal world, doctors would have
a better way to identify which prostate
cancers need to be treated and which
pose no threat. Work to find genetic
and protein markers that characterize
aggressive prostate cancer is under
way. Men whose tumors have these
markers would easily be identified
and treated.
“Until that type of testing is available,
active surveillance will continue to be
a viable option for many patients with
prostate cancer,” says Andriole. “It’s a
management strategy that always can
be re-addressed at any time. Surgery
and radiation therapy are irreversible.”