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New clues in prostate cancer therapy-(USA
TODAY-28/07/2005)
Two new studies could help men and their doctors
better treat prostate cancer. Doctors have struggled for years over how
aggressively to treat prostate cancer, a disease more common than it is
fatal, says Stephen Freedland, an author of one of the articles and a
clinical instructor at Johns Hopkins School of Medicine in Baltimore. A
man has a 17% lifetime risk of being diagnosed with prostate cancer, for
example, but a 3% risk of dying from it. Yet about one in three prostate cancer patients who
have surgery eventually show signs of a relapse, according to a study
published today in the Journal of the American Medical Association. Doctors have few reliable ways, however, to
determine which of these relapses, detected by PSA tests, will be deadly
and which will prove relatively harmless. The article suggests that doctors might be able to
combine three measurements to select those who need strong therapy.
•Time to recurrence: the time it takes after
surgery to detect levels of PSA, or prostate-specific antigen, in the
blood. This protein, which is made by the prostate, should
be undetectable after surgery if a patient is cancer-free. The presence of PSA in the blood after surgery
indicates that some tumor cells remain hidden in the body.
•PSA doubling time: the time it takes for
the PSA level to double after surgery. This measures how quickly the
cancer is growing.
•The Gleason score: a measure of
aggressiveness assigned after examining prostate cancer cells under a
microscope. Scores above 8 are considered the most dangerous.
In the study, men whose PSA doubled in less than
three months survived an average of six years. Among these men, however,
those whose cancer recurred in less than three years and who had Gleason
scores of 8 to 10 survived about three years. After 15 years, no prostate-cancer-related deaths were found in men whose
disease took more than three years to return and whose PSA took more than
15 months to double. Men who are at high risk could benefit from
aggressive treatments, such as hormone suppression and chemotherapy,
Freedland says.
A study in the same journal reported another
potential way to predict which prostate cancers are most worrisome.
Among patients treated with radiation, men had the
greatest risk of death if their PSA increased by more than 2 nanograms per
milliliter in the year before they were diagnosed. Some experts say that doctors need to verify these
results before changing the way they treat patients. Mitchell Anscher, a professor at Duke University
who wrote an editorial accompanying the articles, notes that hormone
suppression and chemotherapy cause serious side effects. Chemo can make patients very sick. Suppressing
testosterone, sometimes called "chemical castration," can cause impotence,
hot flashes and bone loss. "You don't yet know if those treatments are really
going to do (patients) any good," Anscher says.
[Back]
Prostate
Cancer Radiation: Study Shows Many Men Can Still Have
Erections, Avoid Incontinence-(Yahoo News-22/07/2005)
New research shows that most men who get radiation
therapy for early stage prostate cancer can still get an erection and are
not incontinent a year later. The finding appears in the International Journal of Radiation
Oncology, Biology, and Physics. The researchers included Steven Feigenberg, MD, of the radiation
oncology department at Philadelphia's Fox Chase Cancer Center.
Prostate cancer is the No. 2 cause of cancer deaths and the most common
cancer (except skin cancer) among U.S. men, according to the American
Cancer Society (ACS). The odds of getting or dying from prostate cancer rise with age. More
than three out of four new cases are found in men older than 65. Men in
that age range also account for 90% of prostate cancer deaths. Prostate cancers often grow slowly. But, like many cancers (and other
diseases), the sooner it's flagged, the better. Treatment may include
radiation, surgery, or "watchful waiting." Because prostate cancers may advance so slowly, men with early prostate
cancer can opt for watchful waiting. These localized cancers are unlikely
to cause men -- especially older men -- any problems during their
lifetimes, according to the National Cancer Institute.
Surgery to remove the prostate can result in various complications
including urinary incontinence and erectile dysfunction. The risk of
impotence can be reduced by nerve-sparing surgery. Radiation treatment can involve external beam treatment or radiation
emitted from radioactive "seeds" implanted in the prostate (prostate
brachytherapy). Both of these treatments kill cancer and healthy cells.
Urinary problems and erectile dysfunction are also side effects of this
treatment.
[Back]
Early PSA screening may reduce risk of prostate cancer death: study-(Yahoo
News-08/07/2005)
Early screening for prostate cancer in men without symptoms could
significantly reduce their risk of going on to develop an advanced and
usually deadly form of the disease, a Canadian study suggests. Researchers at the universities of Toronto and British Columbia found
that early PSA testing may reduce the risk of metastatic prostate cancer -
the kind that spreads beyond the walnut-sized gland - by more than a
third.
The study compared the PSA testing histories of 236 men with advanced
prostate cancer against those of a control group of men without metastatic
cancer - 462 who either didn't have the disease at all or had a localized
tumour. "What we found was, in fact, that the risk of metastatic prostate
cancer was about 35 per cent less in the men who had been screened," said
study co-author Dr. Vivek Goel, a professor of health policy management
and evaluation at the University of Toronto.
The screening tool is a simple blood test that detects levels of what's
known as prostate specific antigen, or PSA. While small amounts in the
blood are normal, higher levels could indicate cancer. Yet the test remains controversial because it is not foolproof and may
cause undue distress. High PSA levels can exist when no cancer is present
or a tumour may be a type that doesn't spread to other parts of the body,
so men can live normal lives for many years to come. But PSA testing may also flag the type of prostate cancer that will go
on to spread if left untreated, said the researchers.
"Our study . . . adds to the body of evidence that shows that it does
have potential for having a fairly significant effect in reducing the risk
of advanced prostate cancer and, by extrapolation, the death from prostate
cancer," Goel said. That's because detecting prostate cancer before it has spread allows
for early and effective treatment. The study adds weight to the argument that PSA testing should be
routine for men - as mammography and pap smears are for women - not just
when a doctor suspects cancer because of symptoms, he said. "There may be
greater benefit from an organized screening program." But the test, when used strictly as a screening tool, is covered by
only about half of Canada's provincial health plans.
An estimated 20,500 Canadian men will be diagnosed with prostate cancer
this year, and about 4,300 will die. Prostate cancer is the second-highest
cause of cancer death among North American men after lung cancer. "Our study shows a fairly significant benefit for early screening using
the prostate specific antigen test, so these results are important for men
and their doctors," said Dr. Jacek Kopec, professor of health care and
epidemiology at the University of British Columbia and lead author of the
paper.
The head of the Canadian Cancer Society, which helped fund the study,
called the findings welcome news for Canadian men. "The results of this study are interesting and add to the body of
evidence about the PSA test," said Dr. Barbara Whylie. "We look
forward to the results of two other large, ongoing trials to validate
these findings. In the meantime, we
will continue to encourage men to discuss this test with their doctors
until more definitive answers about the benefits of the PSA test are
available."
The study, published in the August issue of the Journal of Urology,
recruited men from the Greater Toronto Area in 1999-2002. They ranged in
age from 45 to 84; the average age of prostate cancer diagnosis was 68. Researchers obtained self-reported information about their lifestyles,
health history and use of health services. They also received permission
to review medical records and history of PSA screening.
[Back]
Prostate cancer screen test flawed, experts say-(Reuters-05/07/2005)
A screening test for prostate cancer taken by millions of men every
year is not terribly accurate and not even the best result ensures that a
man is cancer-free, experts said. They found the standard prostate-specific antigen, or PSA test,
produces many false positives and false negatives -- meaning some men who
think they do not have cancer actually do, while others may undergo
uncomfortable biopsies only to learn there is no tumor after all. "Patients have assumed, 'My PSA is below 4. It's normal. I have no
risk'," Dr. Ian Thompson of the University of Texas Health Science Center
at San Antonio, who led the study, told a news conference.
In fact, some men with PSA levels of 1 had prostate cancer, his study
showed. Others with higher PSA levels did not have prostate cancer. If all men got biopsies when PSA reached 1.1, more than 80 percent of
all prostate cancers would be detected, Thompson said. But 61 percent of
men who got biopsies would turn out not to have cancer. A cutoff of 2.6 would detect only 40.5 percent of cancer cases. This could explain why some men die of prostate cancer despite
intensive screening programs, the researchers said. "This is going to require a re-education not just of patients but of
physicians," Thompson said. "What should men do? Our take home message ...
they should consider the risk factors."
Men whose fathers or brothers had prostate cancer, black men and others
have a higher risk than the general population, for instance, he said. "PSA, like blood pressure, like cholesterol, like many other tests,
shouldn't be considered to be 'normal' or 'abnormal' but should be
considered as showing a range of risk," Thompson said.
For their study, published in the Journal of the
American Medical Association Thompson and
colleagues examined more than 5,000 men who took part in a larger study
that showed the drug finasteride, sold by Merck and Co. under the brand
name Proscar, could help prevent prostate cancer in some men. All the men in the latest study got a placebo instead of finasteride
and they were watched for seven years. At the end, all of them got
biopsies, regardless of PSA level. Nearly 22 percent of the 5,000 men were found to have prostate cancer,
either during the seven years or at the end. The good news was that PSA was accurate in detecting high-grade
prostate cancers -- those more likely to spread a kill a patient.
Prostate cancer affects more than 200,000 men a year in the United
States and will kill 29,000 in 2005, according to the
American Cancer Society. It is usually a slow-growing cancer and older patients often can simply
keep an eye on it because they are likely to die of something else first.
But there is no good way to tell who can safely get away with "watchful
waiting."
An American man has a 17 percent lifetime risk of prostate cancer, but
only a 3 percent risk of dying from it. In 2001 about 75 percent of U.S. men 50 and older reported having at
least one PSA, and 54 percent say they have it measured regularly.
In a separate study, researchers at the American Cancer Society found
that men who use aspirin and other nonsteroidal anti-inflammatory drugs or
NSAIDs have a slightly reduced risk of prostate cancer. But the society said their findings from a study of 70,000 men do not
yet justify taking analgesics primarily to prevent prostate cancer.
[Back]
Effects
of diet on prostate cancer-(Yahoo News-29/01/2005)
Studies show men in Japan and China
have as much as 90 percent less prostate cancer than American men. With
the large number of immigrants in Hawaii from Japan, researchers at the
University of Hawaii set out to determine why this difference exists. Their research involved Japanese-Americans including
first generation immigrants and their offspring. This was known as the
migrant study.What they found was that cancer rates varied between
Japan and Hawaii and that cancer rates varied between generations within
Hawaii.
"Breast cancer
rates are very low in Japan. They're high in the United States and we showed
was that if you looked at the first generation of migrants
in Hawaii, the
Japanese-American women, their breast cancer rates were still
low by U.S. standards
but they were much higher than in the first generation,
so there was a
progression," said lead researcher Dr. Laurence Kolonel.
This, says Kolonel,
is an indication that it can't just be genetics. He believes it's
environmental.
Researchers concluded the likeliest culprit was diet – especially
as more Western
eating habits make their way into Hawaii with fast food
restaurants.
Now, Kolonel and
colleagues at the University of Hawaii are collaborating
with researchers
at the University of Southern California to gather groups of
individuals in
one of the following categories: native Hawaiians from Hawaii,
Caucasians from
Hawaii, Japanese-Americans from Hawaii, African-Americans
from California,
and Latinos from California. Their goals are twofold: see which
components of the
diet increase the risk for cancer and which protect against
cancer; and see
if those relationships are consistent across ethnic groups.
A total of 215,000
individuals are expected to enroll in the study. All filled out a
26-page questionnaire
about their diets and some will have blood and urine
collected as well
to look at biological markers that explain what happens to the
food once it's
absorbed into the bloodstream. The current study has no set end
date but is expected
to go for about 20 years or more to get the maximum
benefit.
"We want to
be able to recommend to the public not just specific suggestions
like 'eat less
fat' or 'eat more fiber,' but what's the kind of diet that you should
eat in general?
What's the sort of pattern you should follow so that you will
hopefully live
a long and healthful life without disability and to a ripe old age?"
Kolonel said.
Dr. Dean Ornish,
inventor of the Ornish diet, has found by eating a diet low in
fat and high in
fruits and vegetables, men can actually lower their risk of
prostate cancer.
He conducted a study where men were randomly assigned to
eat whatever they
wanted and half were asked to make intensive changes to
their diet. "After
three months, PSA levels as a marker for prostate cancer
were essentially
unchanged in the comparison group, but they went down
significantly in
the group that made comprehensive changes in diet and
lifestyle,"
Ornish said.
Radiation Seeds May
Be Enough for Prostate Cancer-(Reuters Health-26/01/2005)
Implanting
tiny radioactive "seeds" in the prostate, a treatment called brachytherapy,
may be all that is needed to combat low-risk forms of prostate cancer, new
research suggests.
Additional treatments, such as radiation from an external source, known
as external beam radiotherapy (EBRT), or reducing testosterone levels,
known as androgen deprivation therapy (ADT), may only be necessary for severe
forms of the disease. The findings appear in the International Journal of
Radiation Oncology, Biology, Physics. "The most important part of the work is that low-risk patients do not
require '(EBRT) or ADT," Dr. Gregory S. Merrick from Wheeling Hospital, in West Virginia told Reuters Health.
"Unfortunately,
a high percentage of low-risk patients unnecessarily receive ADT and some
centers recommend supplemental (EBRT) for all patients" regardless
of prostate cancer severity, he commented. Based on preliminary findings,
"it also appears that (EBRT) will be proven unnecessary in intermediate-risk
patients and once again, ADT is unnecessary in intermediate-risk patients,"
Merrick said.
Merrick
and colleagues evaluated the benefit of adding EBRT and/or ADT to seed therapy
in 227 patients with low-risk prostate cancer, 251 with intermediate-risk
prostate cancer, and 190 with high-risk prostate cancer. As noted, the authors
found no evidence that adding EBRT or ADT to seed therapy improved survival
in the low-risk group of patients and probably not in the intermediate-risk
group either.
For
high-risk patients, however, these added therapies did seem to offer a benefit
beyond that achieved with seed therapy and the researchers plan to look
at this issue further in an upcoming study.
Weight
might affect prostate cancer test-(AP-24/01/2005)
A new study suggests a man's weight may affect the accuracy of a common
test to detect prostate cancer, leading researchers to warn that doctors
could be missing the dangerous cancer in obese men. Researchers at the University of Texas Health Science Center in San
Antonio studied 2,779 men without prostate cancer between 2001-04. In the
study released online in the journal Cancer, they reported finding
that the more obese the men were, the lower their levels of
prostate-specific antigen or PSA. A PSA of 4.0 or lower usually means no
cancer.
Previous studies have shown that
prostate cancer is more aggressive in obese
men than in men of average weight.
The researchers wanted to see if the
cancer's detection was somehow
being delayed in obese men. The Texas study
found that the most morbidly obese
men had about 30 percent lower PSA levels
than men of normal weight. "That
tells us it's likely or it's possible that prostate
cancer detection may be delayed
in overweight or obese men," said Jacques
Baillargeon, associate professor
of epidemiology at the health science center.
The research may encourage many
doctors to take a closer look at the tests of
obese men.
"For sure, I will be more
vigilant in my patients who are obese in evaluating their
PSA," said Dr. Nelson Stone
of Mount Sinai School of Medicine, who was not
involved in the study. "We
may be losing some of the sensitivity of the test in
the obese patient in our ability
to detect prostate cancer. We may have to set
our sights lower."
The antigen used in the screening
test is made by normal prostate cells and is
measured in blood. The higher
the antigen level, the more likely the chance of
prostate cancer, as the cells
multiply uncontrollably, according to the American
Cancer Society. But having high
PSA levels is not a definitive diagnosis of
cancer, which is why the Atlanta-based
society recommends men with high
PSA levels have a biopsy.
The latest study builds on previous
research released in May in the New
England Journal of Medicine that
found that men with a "normal" PSA actually
had cancer 15 percent of the time
and that two-thirds of those men with cancer
had aggressive cases.
The Texas study did not explain
why obese men have lower PSA levels. But
doctors believe obese men produce
more estrogen, which drives down
testosterone levels and could
affect cells that produce the antigen used in the
test.
[Back]
New
Clue to Prostate Cancer May Improve Treatment- (HealthDayNews-
16/11/2004)
New information about the
activity of a hormone-sensitive cell receptor could improve the treatment
of prostate cancer, according to a study in the November issue of Cancer
Cell. Androgen receptors (AR) play a key role in prostate cancer
progression and are a prime target for treatment of the disease. Now,
researchers at the David Geffen School of Medicine at UCLA have discovered
that AR activity is not triggered by molecules called EGFR -- as was
previously believed -- but by another chemical pathway, called HER2/ERBB3.
The finding may explain the limited success
of the EGFR-inhibiting drug Gefitinib, which was recently tested against
prostate cancer in clinical trials. About a third of prostate cancer
patients develop metastatic disease and receive treatment to stop androgen
production and AR activity. However, this treatment eventually becomes
ineffective. The UCLA researchers suggest that drugs that target HER2,
instead of EGFR, may prove more effective in treating these types of
prostate cancers.
[Back]
Quality
of life after prostate cancer diagnosis-(Yahoo News-12/10/2004)
A
study compares quality of life among men treated with either surgery or
radiotherapy for prostate cancer. Previous research has suggested that
radical prostatectomy reduces disease-specific mortality among men with
prostate cancer, compared to 'watchful waiting'. But surgery has a
negative impact on sexual and urinary functioning, and does not improve
overall mortality rates. Radiotherapy is another treatment option and men
with prostate cancer, and their doctors, need information comparing the
outcome and impact of the different treatment plans to make decisions.
Researchers at the National Cancer Institute in the US now report on a
comparison of over 1,000 men having either radical prostatectomy or
radiotherapy.
Five
years after diagnosis overall sexual functioning had declined in both
groups. Two years after diagnosis, however, 82 per cent of those who had
had surgery experienced impotence, compared with 50 per cent of those
having radiotherapy. More patients in the surgery group experienced
urinary problems - 15 per cent - compared to the radiotherapy group - four
per cent. But more men who had radiotherapy had bowel problems than those
in the surgery group. The findings should help guide doctors and their
patients in treatment decisions about prostate cancer.
[Back]
Research
and Markets: Prostate Cancer: New Guidelines and R&D Advancement;
An Analysis of Prostate Cancer Therapeutics: Progress, Developments and
Forecasts-(BUSINESS WIRE-14/09/2004)
Research and Markets has
announced the addition of Prostate Cancer: New Guidelines and R&D
Advancement to their offering. In this issue of Cancer Highlights, the
field of prostate cancer therapeutics is analyzed. The progress in this
field is evaluated and industry related activities are described. Treating
prostate cancer is a complicated task. This fact increases the
possibilities to find business opportunities, which has already been
realized by many who have turned the field of prostate cancer therapeutics
into a highly competitive area. Improved methods for diagnosing prostate
cancer will enhance the market size and make this area even more
interesting in the future.
The year 2004 has been a year
of change in terms of treating patients with prostate cancer. New
guidelines for the use of androgen suppression and possible benefits from
combinations with radiation therapy are described in this report. Subset
analysis has demonstrated a survival benefit from radiotherapy only for
patients with a biopsy Gleason score higher than 6 after short-term
neoadjuvant hormonal therapy. In the April issue of Urology,
GlaxoSmithKline published results indicating that long-term treatment with
Avodart (dutasteride) resulted in a low incidence of drug-related side
effects. The incidence decreased with duration of treatment. Other major
drugs that will be of interest in relation to these findings are Zoladex,
Proscar and Casodex. These are all included in this progression analysis.
The antiandrogens are becoming
an increasingly realistic alternative for future prostate cancer
prevention. Strategies and projects related to cancer prevention and
especially prostate cancer prevention have been studied. A second major
topic is the combination of Aventis' Taxotere in combination with
prednisone. This issue presents the latest data on utilizing a combinatory
therapeutic strategy of docetaxel and different investigational drugs such
as Avastin, Herceptin, GTI-2501, ILX-651, calcitrol, Genasense, Gleevec,
SGN-15, Thalomid and Velcade.
In June 2004, the American
Society of Clinical Oncology (ASCO) released new guidelines for treating
men with androgen-sensitive prostate cancer. Taxotere injection
concentrate in combination with prednisone is moving forth as a treatment
for advanced prostate cancer that is no longer responding to hormonal
therapy. The ASCO expert panel on androgen deprivation therapy (ADT) has
reached the conclusion that the use of nonsteroidal anti-androgens can be
viewed as an alternative to orchiectomy or drug treatment with luteinizing
hormone releasing hormone agonists (medical castration). Since no studies
have satisfactory demonstrated a survival advantage for starting treatment
earlier, the panel feels that no specific recommendations can be issued
regarding the question of early vs. deferred ADT.
Researchers involved in the
Early Prostate Cancer Program have concluded that hormone therapy
initiated immediately following initial therapy reduces the risk of cancer
progression. For men with localized or locally advanced prostate cancer
treated with initial radiation therapy, immediate hormone therapy also
improves progression-free survival.
[Back]
PSA
test saves lives and should not be abandoned, urges Canada's prostate
cancer experts-(Yahoo News-13/09/2004)
The Prostate Cancer Research
Foundation of Canada, the leading national organization devoted solely to
eliminating prostate cancer, warns that a study published in the October
issue of the Journal of Urology may discourage men from taking advantage
of the most important early warning device for prostate cancer -- the PSA
(or prostate specific antigen) test. "The PSA test is the most
valuable tool we have for early detection of prostate cancer," said
John Blanchard, President and CEO of the Prostate Cancer Research
Foundation of Canada, and a recent prostate cancer survivor. "The PSA
test is not perfect. Nor is it designed to say whether a man has prostate
cancer or not. The majority of prostate cancer specialists rely on the PSA
test for early detection and the 95% cure rates that early detection
offers," says Blanchard.
"The PSA test is a very
accurate indicator of cancerous growth in the prostate," said Dr.
Laurence Klotz, Chief of Urology, Sunnybrook and Women's College Health
Sciences Centre in Toronto, and Chair of the Foundation's Scientific and
Medical Advisory Committee. "The PSA test provides physicians with an
early indication of the cancer, and leads to other tests for the disease,
including ultrasounds, biopsies and the Gleason score which evaluates how
aggressive the cancer is. With this diagnostic tool, we can catch the
cancer earlier and increase our number of treatment options."
Prostate cancer afflicts one in
eight Canadian men and their families. About 19,000 Canadian men will be
diagnosed with prostate cancer this year, not including the cases that
develop but go undiagnosed. Over 4,500 Canadian men will die from prostate
cancer this year.
[Back]
Prostate
cancer test under fire. A pioneer of
the procedure says is leading to thousands of needless surgeries-(Yahoo
News-13/09/2004)
A pioneer of the PSA prostate
cancer test taken by millions of men each year now says the test has
virtually no bearing on how much cancer is present. What's more, adds Dr.
Thomas Stamey of Stanford University, the test is leading to thousands of
needless surgeries to remove tiny cancers that may never have become
life-threatening. The PSA, or prostate specific antigen test, measures a
protein produced by the prostate gland. It has been thought that the
higher the blood PSA level, the more likely there is prostate cancer.
Prostates are frequently removed in response to higher than normal blood
PSA levels.
However, a study published in
the October issue of the Journal of Urology concludes elevated PSA levels
are almost always signs of a harmless increase in the size of the
prostate. Stamey and colleagues from Stanford's department of urology
examined tissue samples from more than 1,300 prostates removed by doctors
at Stanford during the last 20 years. They looked at the size and grade of
each tumour, then compared the cancers with the PSA test taken before the
prostate was removed. "In the last five years, only two per cent of
the prostate cancer removed at Stanford had any relationship to PSA,"
says Stamey, a professor of urology.
He published the original
research in 1987 in the New England Journal of Medicine showing increased
blood PSA could be used to detect cancer in the prostate gland. Today,
with PSA screening so widespread, many cancers are being caught earlier.
However, says Stamey, while the test frequently finds cancer today, it
doesn't necessarily mean the need for surgery, radiation, hormonal or
other aggressive treatments that can leave a man impotent and incontinent.
"Every man needs to
recognize that prostate cancer is ubiquitous," Stamey said in an
interview. About eight per cent of men in their 20s have prostate cancer,
and the proportion rises steadily with each decade of life, until 70 per
cent of men have prostate cancer in their 70s. Although we all get it if
we live long enough, it's important to recognize that the death rate is
very small: 226 men per 100,000 over 65 years of age." The death rate
from lung cancer, in contrast, is 30,000 per 100,000 men. His team is
searching for a better blood marker for prostate cancer. In the meantime,
Stamey recommends a yearly digital rectal exam for all men over 50.
Some Canadian cancer
specialists caution against abandoning the PSA test just yet. "A more
logical approach is to suggest we continue with current PSA testing until
a better marker" for the disease is found, says Dr. Chris Morash, a
urologic oncologist at The Ottawa Hospital.
An estimated 20,100 Canadians
will be diagnosed with prostate cancer this year; another 4,300 will die
of the disease.
[Back]
Research
reveals potential new target for prostate cancer drugs UC-(Yahoo News-26/08/2004)
Scientists have determined the
precise molecular structure of a potential new target for treating
prostate cancer, a disease driven in part by abnormal testosterone
activity. The target is part of the androgen receptor, a protein essential
for testosterone to function in human cells. Prostate cancer is the most
common cancer among men. The androgen receptor and testosterone --
technically, 5-alpha dihydrotestosterone -- each drive prostate cancer at
different stages of the disease. A common prostate cancer treatment uses
drugs that compete with testosterone, blocking its ability to bind with
the androgen receptor and so reducing the hormone's effect. But cancer
tends to become resistant to these drugs. The new research provides a
novel strategy to block activation of both the androgen receptor and
testosterone.
UCSF scientists determined the
atom-by-atom topography of the pocket where proteins known as coactivators
bind to the human androgen receptor to enable testosterone to trigger gene
activity. Knowing the detailed shape greatly boosts the likelihood of
developing a drug to block this binding and turn off androgen receptor
activity, the scientists report. The research is being published online
August 24 by Public Library of Science (PLoS) Biology.
"Drugs that block
testosterone binding are not effective in the long term against prostate
cancer," says Robert Fletterick, PhD, UCSF professor of biochemistry
and biophysics and senior author on the PloS Biology paper. "The
shape of the site we have determined -- where coactivators bind to the
androgen receptor -- specifies the design for a new class of drugs. Simple
versions of the 'ultimate' drug will be tested in cancer cells this
year." With an aggressive search for the right chemicals, candidate
drugs might be tested in human patients within three years, he says. UCSF
has filed for a patent revealing the nature of the coactivator site on the
androgen receptor.
The male hormone testosterone
controls development and maintenance of the male reproductive system and
other tissues such as bone and muscle. The hormone is present in smaller
amounts in females, where it also helps form muscle and bones. The
scientists determined the shape of the binding pocket on the androgen
receptor -- technically, the coactivator binding interface -- by exposing
it to billions of randomly chosen protein fragments, or peptides, and
selecting for those that bind best. They then imaged the peptides that
bind best using a technology called X-ray diffraction that shows every
atom of the peptide and the receptor, and how they interact.
The researchers are now testing
the ability of different small molecules to bind to the androgen receptor
binding site. They hope to demonstrate the potential of developing a drug
that will bind more strongly than the normal coactivator, thereby shutting
down androgen receptor activity. Knowing the molecular shape of the target
speeds development of a new drug about ten-fold, Fletterick says, and
helps assure that the drug will work as expected. The new structural
information from the limited number of peptides and small molecules that
bind well to the coactivator sites can be used by chemists to screen from
among thousands of "best-fitting" molecules to find those with
the precise configuration and traits needed for a good drug to block
coactivator binding, Fletterick says. In addition, chemists can use the
information to synthesize new molecules with the required drug traits.
It remains uncertain whether
researchers can identify a small molecule drug candidate that binds to the
androgen receptor more strongly than the coactivators themselves do,
Fletterick cautions. Cancer researchers do not know which coactivators
bind with the androgen receptor when cancer strikes, Fletterick adds. But
the research may lead to selective drugs that permit "good"
activators to bind while blocking those that promote cancer progression.
This possibility is the focus of new research by several UCSF labs. The
highly detailed structure of the coactivator binding site revealed by the
research explains the unusual behavior of this hormone's receptor, says
Eugene Hur, BS, UCSF graduate student in biophysics and lead author of the
scientific paper. Most hormone receptors bind to coactivator sequences
rich in the amino acid leucine, but the androgen receptor is unique in
preferring bigger, bulkier bonding partners. The explanation appears to
lie in the unusually deep binding region, the scientists report.
[Back]
Study
reveals first genetic step necessary for prostate cancer growth- (Yahoo
News-01/09/2004)
A new study from Fred
Hutchinson Cancer Research Center reveals what may be the earliest step in
the development of prostate cancer. The finding could open the door to new
tests that predict whether the cancer will become aggressive and the
development of treatments to prevent the condition from progressing. The
study, published in the Sept. 1 issue of Cancer Research, found that when
mice are engineered to lose a single copy of a gene called Rb in their
prostate, they develop a precancerous condition analogous to the earliest
stages of human prostate cancer. Importantly, in the absence of additional
genetic defects, the mice do not develop full-blown prostate cancer.
This suggests that the loss of
Rb in prostate cells could be the initial spark that in some men
eventually leads to prostate cancer, said senior author Norman Greenberg,
Ph.D., a member of Fred Hutchinson's Clinical Research Division.
"Finding the loss of Rb is like seeing smoke," he said. "We
now need to figure out the genetic predictors for fire."
To identify genetic events that
cause early-stage prostate cancer, Greenberg and colleagues focused on the
Rb gene. The gene is known to be defective in a variety of cancer types,
including up to 60 percent of human prostate cancers. Rb is a member of a
family of genes known as tumor suppressors, which normally work to keep
cells dividing at a healthy pace. Cells with defective or missing tumor
suppressors lose their brakes on cell division, a hallmark of cancer. The
researchers developed a system using mice that were genetically engineered
to self-destruct one or both copies of its Rb gene in prostate cells. The
important difference between these mice and the standard gene knock-out
strategy is that the Rb gene stays intact in all other tissues of the
animal, a situation that closely resembles how genes are inactivated or
lost in cancers that occur sporadically in humans.
The scientists found that upon
losing even one copy of the Rb gene in prostate cells, mice developed a
condition known as focal hyperplasia, characterized by precancerous
growths. Nearly a year after they formed, the growths did not become
cancerous. "This suggests to us that loss of a single copy of Rb can
initiate this excess cell growth but is not sufficient for cancer to
develop," Greenberg said. "Perhaps the most significant finding
was that loss of the second copy of Rb – an event previously thought to
be essential for tumor progression – did not appear to accelerate the
disease. Losing one copy was enough to get things going."
While Greenberg had previously
demonstrated that combined loss of Rb and related proteins and the p53
tumor suppressor would predispose mice to develop aggressive prostate
cancer, the role of Rb in tumor initiation remained enigmatic. Further
research is needed to determine which secondary mutations can push these
early stage growths into prostate cancer. Greenberg said that tests to
distinguish between men who only have Rb mutations and those who have
acquired additional genetic defects could help doctors decide when or
whether aggressive treatment is warranted. "Right now, there is no
way to absolutely predict at an early stage whether a man's prostate
cancer is slow-growing and non-lethal, meaning that many men receive
unnecessary treatment that can cause serious side effects," he said.
Scientists have had a difficult
time establishing the causal relationship between genes and cancer,
Greenberg said. "We've addressed this by using a mouse system that
allows us to selectively eliminate genes in the epithelial cells of the
prostate. Our experimental approach allows us to closely mimic what
happens in man and gives us a glimpse into the natural history of the
disease that we haven't had before." Greenberg developed a widely
used genetically engineered strain of mice that develops prostate cancer
at the Baylor College of Medicine prior to joining Fred Hutchinson in
January. "These models represent a new frontier in cancer research
because they give us a better insight into what specific genes really do
in a live mammal," he said. "The mice give us a highly
reproducible glimpse at the earliest forms of cancer – those rarely seen
in the clinic – and therefore can be used to develop new markers for
detection as well as new strategies for prevention and early
intervention."
Prostate cancer is the second
leading cause of death for men in the United States. This year, more than
230,000 men will be diagnosed with the disease, in large part due to
widespread screening with the prostate-specific antigen, or PSA, test. The
test has been controversial because it cannot distinguish between men who
have non-progressing forms of the disease that may never cause harm and
those who have aggressive cancers that require treatment. Researchers are
eager to develop tests that can stratify early stage prostate cancers by
their likelihood to worsen, an achievement that could spare many men from
unnecessary surgery or radiation therapy.
With this in mind, Greenberg
said his next goal is to identify the additional mutations - such as occur
in p53 or other tumor suppressor genes - that must collaborate with Rb to
drive the benign condition to cancer. Ideally, blood or other simple tests
to detect these mutations could be developed that reveal predictive
information about a man's type of cancer well before he is in danger.
"The idea is to set the bar for detection as early as possible,"
Greenberg said. "Ideally, we'd hope that a man diagnosed at an early
age with prostate cancer could be assured that his cancer wasn't likely to
progress or that he needed early intervention that could save his
life."
[Back]
Protein
Prompts Spread of Prostate Cancer-(HealthDayNews
-23/08/2004)
A protein called hepsin
promotes the spread of prostate cancer by causing disruption of tissue
organization, says a study in the August issue of Cancer Cell. This
finding could lead to the development of new drugs that inhibit hepsin and
slow prostate cancer's spread. Scientists at the Fred Hutchinson Cancer
Research Center in Seattle created mice with elevated hepsin levels in the
prostate gland and found these mice had marked tissue disorganization of
the prostate gland, specifically in a structure called the basement
membrane. These mice developed more advanced tumors and had more spread of
cancer to the liver, lung and bone.
"We have found that
increase in hepsin expression leads to disorganization of the basement
membrane and promotes primary prostate cancer progression and
metastasis," researcher Dr. Valeri Vasioukhin said in a prepared
statement."Since hepsin is an enzyme, it should be relatively easy to
develop drugs specifically inhibiting hepsin activity. Previous research
demonstrated that hepsin is not critical for normal cells within the body
and, therefore, inhibition of hepsin with drugs is unlikely to have
significant side effects," Vasioukhin added.
[Back]
Exercise
May Beat Fatigue in Prostate Cancer-(Reuters Health -18/08/2004)
Staying active through moderate
walking may help prevent fatigue in men undergoing radiation therapy for
prostate cancer, a UK study shows. Cancer patients commonly develop
fatigue as the stress of the illness and the physical effects of treatment
take their toll. It's common for patients undergoing treatment to be told
to take it easy, and some may self-impose limits on their daily
activities, according to the study's lead author Dr. Phyllis M. Windsor.
But in her team's study of 66
men with cancer confined to the prostate gland, those who were physically
active during their month of radiation treatment showed no substantial
increase in fatigue. The same was not true of patients in the
non-exercising "control" group, according to findings published
in the August issue of the journal Cancer. The findings are in line with
research with women undergoing radiation and chemotherapy for breast
cancer, noted Windsor, a cancer specialist at Ninewells Hospital in
Dundee, Scotland. It's thought, she told Reuters Health, that such results
"potentially apply to all groups of patients with cancer."
While rest may be the intuitive
response to fatigue, too much inactivity can make the problem worse. Long
periods of rest, Windsor said, may de-condition muscles and roll back a
person's capacity for exercise, making even routine daily tasks tough to
tackle. Exercise, on the other hand, keeps muscles conditioned, so that
everyday activities require less effort and are less taxing on the body.
In addition, Windsor pointed out, research suggests that exercise combats
depression, which can alter patients' perceptions of fatigue.
For the current study, the
researchers randomly assigned 66 men with localized prostate cancer to
either an exercise group or a control group. The exercisers walked at a
moderate pace for 30 minutes, three days per week; patients in the control
group were not discouraged from performing their usual activities, but
were told to rest if they became tired. After four weeks of radiation
therapy, men in the control group were had greater fatigue than they did
before treatment; and one month later, these patients were still showing
signs of weariness. In contrast, exercisers showed no significant increase
in fatigue at any point during the study, according to the researchers.
Windsor said she and her colleagues are planning a larger study to see if
walking or, for patients who cannot walk, chair-based exercises can
counter fatigue in patients with a range of cancers, including prostate,
cervical, uterine, bladder and kidney cancers.
[Back]
Study
narrows search for genes placing men at increased risk for prostate cancer-(Yahoo
News-18/08/2004)
Scientists at the Translational
Genomics Research Institute (TGen), Johns Hopkins Medical Institutions,
the National Institutes of Health, The University of Michigan and five
other research institutes world-wide announced today the findings from the
largest study of the genetics of prostate cancer undertaken to date.
Results have zeroed in on three different regions of the genome containing
genes that may make men more vulnerable to this common cancer. Prostate
cancer is the second-leading cause of cancer death in US men. The findings
appear in the August 18 issue of the Journal of the National Cancer
Institute. The researchers are currently scouring those genome regions,
culled from more than 400 cancer-prone families, to identify specifically
which genes lead to increased prostate cancer susceptibility.
"This study will help us
predict better who is at the highest risk for this disease," says the
paper's lead author, Dr. Elizabeth Gillanders, a scientist at the National
Institutes of Health in Bethesda, MD. "If we could identify men with
susceptibility genes, we can target our surveillance to them and identify
their cancers much earlier. Early-stage treatment is far more beneficial
in prostate cancer," she says. In addition, she noted, prostate
cancers in men who possess susceptibility genes tend to be more
aggressive--and more often fatal--than prostate cancers in men who are not
genetically prone to the disease. "This study focuses and intensifies
the hunt for genes that increase a man's risk of prostate cancer,"
says the paper's senior author, Dr. Jeffrey M. Trent, Scientific Director
of TGen in Phoenix, Arizona. "We needed this sort of massive study in
order to have the power to target important genome regions."
"The difference between
this paper and previous work on the genetics of prostate cancer is the
number of families studied," says Dr. William B. Isaacs, of the Johns
Hopkins University in Baltimore, MD, principal investigator for the
project. "There has been much confusion and difficulty in trying to
figure out where we should be looking for these genes." Today's paper
reports on data from approximately 2,000 individuals from over 400
families.
"The large number of
prostate cancer families utilized in this study allowed us to overcome the
challenges we have faced in this field for the past few years," says
Dr. Jianfeng Xu, one of the lead authors on the paper and a researcher at
Wake Forest University School of Medicine. "This study shows that
hereditary prostate cancer genes exist and demonstrates that by working
together, teams of researchers are able to locate these genes. These
results give us a renewed confidence in our search for prostate cancer
genes."
[Back]
Study:
Test predicts prostate cancer's aggression-(AP-08/07/2004)
Prostate cancer is much more
likely to kill if a man's PSA level rises rapidly before the cancer is
even diagnosed, according to a study that suggests a new and far more
meaningful way of looking at PSA test results. The
finding could help patients and doctors make the often difficult decision
of whether to undergo surgery or merely wait and watch. The PSA test is
widely used to diagnose prostate cancer by measuring levels of a substance
called prostate-specific antigen in the blood. Up to now, doctors have
focused largely on the PSA level itself, and not on how it changes over
time. But researchers at Brigham and Women's Hospital and elsewhere found
how fast PSA level increased in the year before prostate cancer was
diagnosed predicts which tumors are deadly nearly 10 times better than the
PSA level itself. "The study is pretty definitive," said lead
researcher Dr. Anthony D'Amico, a radiation oncologist at Brigham and
professor of radiation oncology at Harvard Medical School. "It's not
the level of PSA that matters, it's the change from year to year."
The finding underscores the importance of getting regular PSA screenings,
so that doctors can spot trends.
When doctors find prostate
cancer, they often recommend "watchful waiting" over
prostate-removal surgery, because the operation can cause impotence and
incontinence and because some prostate tumors are so slow-growing that men
die of something else before the cancer kills them. But most men do not
want to wait, so doctors are seeking better ways of predicting which
tumors will be lethal.
PSA levels alone are not always
reliable. A recent study found the tests missed about 15 percent of
prostate cancers in older men whose readings were supposedly normal --
that is, at or below a count of 4. The new study, reported in Thursday's
New England Journal of Medicine, followed 1,095 men, 65 years old on
average, who had prostate cancer; they received PSA screenings at least
once a year and underwent prostate surgery between 1989 and 2002.
Twenty-eight percent of the men whose level rose more than 2 points the
year before diagnosis died of prostate cancer within seven years --
despite having the gland and adjacent lymph nodes and seminal vesicles
surgically removed. D'Amico said the
findings make clear which patients need aggressive treatment, but not
which ones can safely be monitored through repeated testing.
PSA is a protein that helps
liquefy semen for ejaculation. An elevated PSA level can indicate benign
prostate enlargement or prostate cancer. So when a man is found to have an
elevated PSA level, doctors do a biopsy, withdrawing cells from the gland
by needle for examination under the microscope for signs of cancer.
Guidelines call for annual PSA tests beginning at age 50 - or 45 for men
with a family history of prostate cancer. D'Amico said a baseline PSA
level should be determined at age 35 to spot changes.
Dr. Mark Jordan, professor and
chief of urology at University of Medicine and Dentistry of New Jersey in
Newark, said he believes the initial PSA level, and the percentage
increase, are just as important as the rate of increase, or PSA velocity,
but there are not enough guideposts for deciding on surgery. "We're
not even sure if prostate cancer surgery prolongs life," said Jordan.
Dr. Howard Parnes, chief of the
National Cancer Institute's prostate and urological cancer research group,
said a high PSA velocity indicates substantial risk of relapse after
surgery and death. But he said larger studies with longer follow-up are
needed. Parnes and D'Amico said the PSA velocity can be used now to
identify which high-risk men could participate in studies of such
treatments as radiation, hormones to suppress testosterone and cancer
drugs that could be given in addition to surgery.
Prostate cancer is the No. 2
cancer killer among men, with an estimated 30,000 deaths and 230,000 new
cases each year, according to the American Cancer Society. Despite that,
only about 60 percent of American men over 50 have had a PSA screening.
Men have a one-in-six lifetime risk of getting prostate cancer. However,
the death rate has fallen nearly 20 percent since the PSA test became
widely used in the mid-1990s, a drop attributed to both earlier detection
and better treatment.
Dr. William J. Catalona of
Northwestern Memorial Hospital, who worked with D'Amico and helped develop
the PSA test to determine risk of prostate cancer, said he thinks a biopsy
should be done once the PSA level hits 2.5 or PSA velocity reaches 0.75 --
as the National Comprehensive Cancer Network recently recommended.
[Back]
Tools
for prostate-cancer recovery-(Yahoo News-20/07/2004)
Psychologist teams
with doctor to help patients and their families cope with treatment side
effects As many prostate-cancer survivors have discovered, the lifesaving
benefits of surgery, radiation and hormone therapy can come with a cost.
All three treatments may bring on sexual dysfunction and urinary incontinence.
In addition, by depriving the body of testosterone, long-term hormone
therapy can blunt a man's sex drive, sap his energy and trigger mood swings.
These and other quality-of-life
adjustments affect patients as well as their partners and aren't easily
resolved in the doctor's office, says Tia Higano, M.D., a University of
Washington (UW) prostate-cancer specialist and associate in clinical research
at Fred Hutchinson. Higano decided she wanted to do more to help. She
found her answer in UW psychologist Sylvie Aubin, Ph.D. Aubin sits in
on Higano's patient consults and offers prostate-cancer patients and their
partners a "toolbox" of strategies to cope with challenges that are often
hard to talk about. They see their patients at the Seattle Cancer Care
Alliance, a patient-care partnership of Fred Hutchinson, the UW and Children's
Hospital and Regional Medical Center located on the Fred Hutchinson campus.
"Men can live a long time after treatment for prostate cancer, and they
deserve to have a good quality of life," said Aubin, an acting instructor
in the UW Department of Psychiatry and Behavioral Sciences. "But it's
often very hard to get men to open up about these problems, which is the
first step. Once I open the door for them to do that, my role is to be
a 'tool person' -- to provide patients and partners with a collection
of strategies to help them deal with these challenges." Aubin and Higano
plan to measure the benefits of those interventions in the coming months
in a research study.
[Back]
Today's
Prostate Cancer Treatments More Aggressive, Successful Says American Society
for Therapeutic Radiology and Oncology-(US Newswire-14/07/2004)
In recent years,
doctors have become more willing to treat prostate cancer more aggressively
with radiation therapy, and as a result, more patients are being cured
of their cancer, according to a new study published in the July 15, 2004,
issue of the International Journal of Radiation Oncology, Biology, Physics,
the official journal of ASTRO, the American Society for Therapeutic Radiology
and Oncology. A 1999 Patterns of Care survey reviewing the records of
more than 550 patients from 58 institutions across the United States shows
that in comparison to surveys from 1989 and 1994, radiation oncologists
are using higher doses of external beam radiation therapy to treat both
earlier stages and more aggressive forms of prostate cancer. In 1999,
45 percent of prostate cancer patients were treated with higher doses
of radiation therapy compared to 3 percent in both 1989 and 1994.
In the study, researchers
learned that the results of clinical trials have persuaded many radiation
oncologists today to add androgen deprivation therapy to radiation therapy
to treat more aggressive or well-established cancers. Further, there has
been a significant increase in the use of CT-based treatment planning
and conformal radiation therapy for treatment delivery. "This is an important
study because it looks at changing trends over many years in the use of
radiation therapy for curing prostate cancer in the United States," said
Michael J. Zelefsky, M.D., lead author of the study and a radiation oncologist
at Memorial Sloan-Kettering Cancer Center in New York. "After careful
analysis, we have learned that in general, more radiation oncologists
are applying the results of clinical trials, which have taught us to use
higher dose levels of radiation and integrate hormone therapy in conjunction
with radiation therapy to achieve more successful outcomes for prostate
cancer patients. In short, the trends are demonstrating more precise delivery
of high dose treatment."
[Back]
Alternative
hormone-blocker reduces side effects in prostate cancer patients-(Yahoo
News-28/06/2004)
An alternative way
of blocking androgen activity in prostate cancer patients produces fewer
side effects and may be a better choice than standard hormone therapy
for some patients. In the July issue of the Journal of Clinical Oncology,
researchers from the Massachusetts General Hospital (MGH) describe how
patients taking bicalutamide, which inhibits androgen activity by binding
to the hormones' receptors, had improved bone density and reported fewer
unpleasant side effects than did those taking leuprolide, a traditional
form of hormone therapy that markedly lowers androgen levels. "The differences
between the two groups were dramatic; bone mineral density increased among
men taking bicalutamide while men in the leuprolide group lost bone,"
says Matthew Smith, MD, PhD, of the MGH Cancer Center, who led the study.
Since the male hormones
called androgens can accelerate the development of prostate cancer, reducing
their activity is a standard part of treating the disease. Most commonly
this is done with drugs like leuprolide, called gonadotropin releasing
hormone (GnRH) agonists, that stop the body's production of all sex hormones.
However, totally blocking hormone activity can lead to potentially serious
side effects such as loss of bone density, which increases the risk of
fractures. Earlier studies by this MGH research team also showed that
GnRH-agonist treatment often leads to unwanted weight gain and increased
body fat. Because bicalutamide blocks androgen activity in a way that
does not reduce hormone levels in the blood, the research team wanted
to see if using a single-drug treatment plan might avoid or reduce side
effects. Earlier research had shown that bicalutamide alone is as effective
as GnRH agonists for men with locally advanced prostate cancer.
The investigators
enrolled 51 men with nonmetastatic prostate cancer who were randomly assigned
to receive either bicalutamide or leuprolide treatment for one year. Although
the participants knew which treatment they received, since the drugs are
adminstered differently, those who gathered and analyzed the study's data
did not know which patients were in which group. At the end of the study
period, blood levels of testosterone and the female hormone estradiol
had risen significantly in the bicalutamide group but fallen in those
receiving leuprolide. Bone mineral density, which decreased in the leuprolide
group, had increased in participants receiving bicalutamide. While both
groups had increases in body fat and decreased lean body mass, those changes
were more pronounced in those receiving leuprolide. And unpleasant side
effects - such as hot flashes, fatigue and sexual effects - were reported
less frequently in men taking bicalutamide. "Bicalutamide monotherapy
may be an attractive alternative to standard hormone therapy for some
men with non-metastatic prostate cancer," says Smith, who is an assistant
professor of Medicine at Harvard Medical School. While bicalutamide is
approved as monotherapy for prostate cancer in 55 countries, in the U.S.
it is only approved in combination with GnRH-analog therapy.
[Back]
Prostate
cancer study boosts radiation therapy-(Yahoo News-26/06/2004)
Prostate cancer
patients who receive radiation therapy within six months of surgery typically
live longer than patients who don't receive early radiation treatment,
a new Italian study finds. "Our results show that radiation therapy after
prostate surgery helps limit the chances that the cancer will recur, allowing
patients to live longer,' said Dr. Cesare Cozzarini, a radiation oncologist
at San Raffaele H. Scientific Institute in Milan, and the study's principal
investigator. "To my knowledge, this is the largest study of its kind
completed at a single institution,' he added.
The researchers examined
the records of 415 men with prostate cancer who underwent surgery to remove
their prostate and surrounding lymph nodes between 1986 and 1999 at the
institute. Two groups of postsurgical patients were studied -- one group
included men who received external beam radiation therapy within six months
of their prostate operation, and the other included men whose physicians
followed them over time and provided radiation therapy only if their cancers
showed signs of returning. None of the men whose records were studied
had metastatic disease -- that is, cancer in areas of the body other than
the prostate. After eight years of follow-up, the survival rate for men
receiving early radiation therapy was 69 percent, compared to 31 percent
for those who had radiation therapy more than six months after their surgeries
or not at all. The researchers also found that the disease remained localized
in the prostate for 93 percent of the patients in the early radiation
therapy group, compared to 63 percent in the other group. The risk of
death from localized prostate cancer was also significantly lower for
men receiving postsurgical early radiation therapy.
[Back]
Thalomid(R)
in Major Peer-Reviewed Journal Publication of Clinical Data From Randomized
Phase II Trial in Androgen-Independent Prostate Cancer-(Yahoo News-01/07/2004)
Celgene Corporation
today announced the results of a randomized Phase II trial conducted by
the National Cancer Institute (NCI). This trial used thalidomide in combination
with docetaxel (taxotere) versus docetaxel alone in patients with metastatic
androgen-independent prostate cancer (AIPC), and is published in the July
1, 2004 issue of the Journal of Clinical Oncology (JCO), a major peer-reviewed
journal.
Prostate cancer is
the most diagnosed cancer in American men and the second leading cause
of cancer death. During 2004, an estimated 220,900 men will have prostate
cancer diagnosed, and 32,500 men will die of this disease in the United
States. This Phase II clinical study investigated the combination of docetaxel
at 30mg/m2 intravenously every week for three weeks plus thalidomide at
200 mg orally each day versus docetaxel at 30mg/m2 intravenously every
week for three weeks in patients with AIPC. The data from this clinical
study reported that the proportion of patients with a greater than 50%
decline in prostate-specific antigen (PSA) was higher in the thalidomide/docetaxel
group, 53% in the combined group and 37% in the docetaxel-alone arm. The
median overall survival in the thalidomide plus docetaxel group was 28.9
months compared to 14.7 months in the docetaxel-alone group. At 18 months,
overall survival in the thalidomide/docetaxel group was 68.2% compared
to 42.9% in the docetaxel-alone arm (P =0 .11 for the overall difference).
The median progression-free survival in the thalidomide/docetaxel group
was 5.9 months compared to 3.7 months in the docetaxel-alone group (P
=0 .32). "This Phase II clinical data demonstrated that thalidomide in
combination with docetaxel may be a future option in the clinical treatment
of androgen-independent prostate cancer," said Dr. Sol J. Barer, Ph.D.,
President and Chief Operating Officer of Celgene Corporation. "Based on
the preliminary results, from this National Cancer Institute study, we
will advance clinical investigation of thalidomide, and other Celgene
immunomodulatory agents such as REVLIMID and ACTIMID, in this severe and
life-threatening form of cancer."
About the Phase II
Study This was an open-label, randomized, phase II study of docetaxel
plus thalidomide versus the docetaxel alone in patients with metastatic
AIPC. A total of 75 patients were enrolled in this trial, with 25 patients
in the docetaxel alone arm and 50 patients in the combination arm. Seventy-five
patients with chemotherapy-naive metastatic AIPC were randomly assigned
to receive either docetaxel 30 mg/m2 intravenously every week for 3 consecutive
weeks, followed by a 1-week rest period (n = 25); or docetaxel at the
same dose and schedule, plus thalidomide 200 mg orally each day (n = 50).
PSA consensus criteria and radiographic scans were used to determine the
proportion of patients with a PSA decline, and time to progression. After
a median potential follow-up time of 26.4 months, 40 patients are currently
alive. The proportion of patients with a greater than 50% decline in PSA
was higher in the thalidomide/docetaxel group (53% in the combined group,
37% in the docetaxel-alone arm). The median overall survival in the thalidomide
plus docetaxel group was 28.9 months compared to 14.7 months in the docetaxel-alone
group. At 18 months, overall survival in the thalidomide/docetaxel group
was 68.2% compared to 42.9% in the docetaxel-alone arm (P =0 .11 for the
overall difference). The median progression-free survival in the thalidomide/docetaxel
group was 5.9 months compared to 3.7 months in the docetaxel-alone group
(P =0 .32). Toxicities in both groups were manageable after administration
of prophylactic low-molecular-weight heparin was used to prevent venous
thrombosis. The combination of thalidomide/docetaxel was clinically tolerated.
Safety Notice If
thalidomide is taken during pregnancy, it can cause severe birth defects
or death to an unborn baby. Thalidomide should never be used by women
who are pregnant or who could become pregnant while taking the drug. Even
a single dose, one capsule (50 mg, 100 mg and 200 mg), taken by a pregnant
woman can cause severe birth defects. Because thalidomide is present in
the semen of male patients, males receiving thalidomide must always use
a latex condom during sexual contact with women of childbearing potential
even if he has undergone a successful vasectomy.
Thalidomide can only
be marketed under a special restricted distribution program. This program
is called the "System for Thalidomide Education and Prescribing Safety"
(S.T.E.P.S.(R)). Under this program, only registered prescribers and pharmacists
may dispense the drug. In addition, patients must be advised of, agree
to and comply with the requirements of S.T.E.P.S. Thalidomide is known
to cause nerve damage that may be permanent. Peripheral neuropathy is
a common, potentially severe, side effect of treatment with thalidomide
that may be irreversible. Decreased white blood cell counts, including
neutropenia, have been reported in the clinical use of thalidomide. In
placebo controlled clinical trials of HIV-seropositive patient populations,
there have been reports of increased plasma HIV RNA levels associated
with thalidomide therapy. The most common adverse events observed in clinical
use in ENL and HIV-seropositive patient populations are rash, maculo-papular
rash, drowsiness/somnolence, peripheral neuropathy, dizziness/orthostatic
hypotension, neutropenia, and increased HIV-viral load. Patients should
be advised about these associated adverse events and routinely monitored
by a physician during treatment with thalidomide.
About THALOMID THALOMID
(thalidomide), manufactured by Celgene Corporation, received U.S. Food
and Drug Administration (FDA) clearance on July 16, 1998 for the acute
treatment of cutaneous manifestations of moderate to severe erythema nodosum
leprosum (ENL) and as maintenance therapy for prevention and suppression
of the cutaneous manifestations of ENL recurrence. Thalidomide is not
indicated as monotherapy for ENL treatment in the presence of moderate
to severe neuritis. Thalidomide currently has a pending regulatory application
(NDA) under review by the Food and Drug Administration (FDA) to confirm
efficacy and safety for use in multiple myeloma, thalidomide is not presently
indicated or approved by the FDA for use in this disease or any other
related cancer.
About Prostate Cancer:
Prostate cancer is the most diagnosed cancer in American men and the second
leading cause of cancer death. Prostate cancer is twice as common and
has more than twice the mortality rate in African-American men than in
Caucasian men. The 5-year survival rate for patients whose cancer is caught
while still confined to the prostate is 99% while the 5-year survival
rate for those diagnosed with distant (metastatic) disease is 30.9%. In
the U.S. alone, nearly 220,900 men will be diagnosed with prostate cancer
this year equaling one man diagnosed every three minutes. It is estimated
that more than 32,500 men in the U.S. will die of prostate cancer. Prostate
cancer affects one in eight American men.
[Back]
Popular
Painkiller May Slow Prostate Cancer Cox-2 Inhibitors -- Such as Celebrex
-- May Delay, Prevent Cancer Progression-(Yahoo News-11/06/2004)
The commonly prescribed
painkiller Celebrex may slow prostate cancer growth, new research shows.
Drugs known as Cox-2 inhibitors, including Celebrex, have been shown to
have anti-tumor effects on a variety of different cancer tissues, including
colon, breast, lung, and prostate cancers, explains researcher J. Eric
Derksen, MD, a urologist with the University of North Carolina at Chapel
Hill. Cox-2 inhibitors (commonly used to treat arthritis) relieve pain,
inflammation, and swelling by blocking the body's production of an enzyme
called Cox-2. These drugs, which also include Bextra and Vioxx, are less
irritating on the stomach lining than earlier versions of anti-inflammatory
drugs, like ibuprofen.
Recent research involving
men treated for prostate cancer has shown especially promising results,
says Derksen, who presented his findings at the American Society of Clinical
Oncology's annual meeting this week in New Orleans. In his study, Derksen
enrolled 24 men who had rising PSA (prostate-specific antigen) levels,
a marker for prostate cancer growth, despite treatment with radiation
therapy or prostate removal surgery. The men took either 400 milligrams
or 800 milligrams of Celebrex for one year. Their PSAs were checked at
several points during that year. Celebrex had a positive effect on nearly
all (92%) of the men after three months, reports Derksen. Overall, PSA
declined in eight of the men and remained the same in three. The rise
in PSA levels slowed in 11 men, indicating that their prostate cancer
was growing more slowly. The two remaining men had no improvement at three
months but the rise in their PSA levels slowed by one year.
It's a hopeful finding:
The other option involves shutting down production of male sex hormones
-- usually with medication -- which has not proven successful in slowing
prostate cancer or improving a man's chances of survival. Also men in
the early stages of prostate cancer recurrence, such as the men in this
study with rising PSA levels, usually have no symptoms. Therefore, shutting
down production of male sex hormones could unnecessarily expose them to
side effects, say the researchers. "These results show that Cox-2 inhibitors
may help delay or prevent [prostate cancer] progression in these patients,"
he writes.
[Back]
Soy
Product May Help Fight Prostate Cancer-(ET-13/06/2004)
Cancer researchers
at U.C. Davis are testing a new compound derived from soy beans and shitake
mushrooms as a possible new tool to battle prostate cancer. Genistein
concentrated polysaccharide (GCP) is already widely used as a complementary
therapy for prostate cancer in Japan and Korea. The Davis scientists are
testing GCP on men in the so-called watchful waiting stage of prostate
cancer. "We're only going to treat patients who are in active surveillance.
In other words, they would diagnose the prostate cancer but do not want
any active treatment," Dr. Ralph deVere White told KCBS reporter Patti
Reising.
White is director
of the U.C. Davis Cancer Center, as well as a professor and chair of urology
at U.C. Davis School of Medicine. "We think this will allow us to absolutely
prove whether this really is a reasonable treatment for patients who are
diagnosed with a very low grade, low-volume prostate cancer," said White.
A company which manufactures and distributes GCP, Amino Up Chemical Co.,
Ltd. of Japan, sponsored the research. "I give great credit to them, White
said. "They're really allowing us to test it." White said the initial
results have looked promising, although the university is still searching
for other men willing to volunteer in the study. "It does look like the
mixture has some benefit, he said.
[Back]
Selenium
May Protect Against Prostate Cancer-(Reuters Health-04/05/2004)
Use of supplements
containing selenium may reduce the risk of advanced prostate cancer, new
research suggests. The fact that no effect was seen against early prostate
cancer suggests that selenium works by slowing cancer progression rather
than by preventing it all together. The current study is one of several
recent looks at the link between selenium levels and prostate cancer.
"Our study is the largest in terms of the (number of participants) and
the follow-up period," lead author Dr. Haojie Li, from Harvard Medical
School in Boston, told Reuters Health. As reported in the Journal of the
National Cancer Institute, the researchers analyzed data from men enrolled
in the Physicians' Health Study.
When the study began,
the men, who were cancer-free at the time, gave blood samples that were
tested for selenium among other things. Selenium levels from 586 men who
later developed prostate cancer were compared with levels from 577 similar
men who didn't develop prostate cancer. Men with the highest selenium
levels were 48 percent less likely to develop advanced prostate cancer
than men with the lowest levels. Moreover, this association was observed
for men diagnosed before and after PSA testing to detect early prostate
cancer came into widespread use in October 1990. High selenium levels
were linked to a reduction in the overall risk of prostate cancer, Li
said. "However, on further analysis, only the association with advanced
cancer," was statistically significant, not early cancer. A specially
designed study, "known as the Selenium and Vitamin E Cancer Prevention
Trial (SELECT), is underway," Li noted, and this should definitively answer
whether selenium use is beneficial in preventing prostate cancer.
[Back]
High
Hormone Levels Linked to Prostate Risk-(Reuters-09/05/2004)
Men over 50 who have
higher levels of testosterone have a higher risk of prostate cancer, U.S.
researchers reported. The findings may mean that men should be cautious
about a new kind of treatment called testosterone replacement therapy,
being tested in older men who see a decline in general health and vigor.
A study of more than 750 men showed those with the highest levels of free
testosterone in the blood were the most likely to have prostate cancer.
"Since testosterone replacement therapy increases the amount of free testosterone
in the blood, older men considering or receiving testosterone replacement
should be counseled as to the association until data from long-term clinical
trials becomes available," said Dr. Kellogg Parsons, a urologist at Johns
Hopkins University who led the study, said in a statement.
The association between
free testosterone and prostate cancer risk in older men was not affected
by height, weight, percent of body fat or muscle mass, Parsons told a
meeting of the American Urological Association in San Francisco. A second
study presented at the same conference found that obese men may be more
likely to see their prostate cancer come back after surgery. Another Johns
Hopkins team found that obese men are more likely than men with normal
weight to have high levels of prostate specific antigen, or PSA. PSA is
produced by prostate cells and is overproduced when the prostate becomes
cancerous. "Our results show that moderately and severely obese men were
at an increased risk for high PSA levels after surgery and therefore are
likely to have prostate cancer recurrence," said Dr. Stephen Freedland,
who led the study. His team studied 1,106 patients treated at five Veteran's
Administration and military hospitals across the country. "Our findings
add to the burgeoning list of chronic and deadly diseases associated with
obesity and underscore the importance of this major public health problem,"
Freedland said.
Obesity is also linked
with pancreatic, breast and colon cancer, as well as heart disease and
diabetes. Prostate cancer affects 221,000 American men a year and kills
29,000.
[Back]
Long-Term
Cancer Survival Data Utilizing ONCURA's OncoSeed(TM) Reinforces Brachytherapy's
Position as Standard of Care for Treating Prostate Cancer- (PRNewswire-28/04/2004)
As the global leader
in minimally invasive prostate cancer treatment, ONCURA(TM) is committed
to research and development that results in improved outcomes for patients
treated with prostate brachytherapy. Fifteen-year data exclusively utilizing
ONCURA's OncoSeed (Iodine-125 Seeds) were recently presented by John Blasko,
MD, Medical Director of the Seattle Prostate Institute at the Institute's
7th annual Seattle Prostate Institute meeting. "At fifteen years after
Iodine-125 brachytherapy, only 4% of patients had died from prostate cancer,"
said John Blasko. "The release of this data further confirms brachytherapy
as a leading prostate cancer treatment option." "The presentation of long-term
survival data that's only available for ONCURA's Iodine-125 products will
encourage other physicians to offer prostate brachytherapy to their patients,"
said John Jeans, Chairman of ONCURA. He added, "Advances such as ONCURA's
RAPID Strand(TM), which is routinely used by the Seattle Prostate Institute,
are expected to improve results even further."
Long-term data supporting
prostate brachytherapy with RAPID Strand were presented at the European
Association of Urology meeting in Vienna. Mr. Stephen Langley, Consultant
Urologist at St Luke's Cancer Centre, Guildford, UK, presented results
of their five-year follow-up, with 93% of patients disease free at this
time. These results indicate that prostate brachytherapy has now become
a routine and successful option for patients in Europe as well as the
US. "Our commitment to prostate brachytherapy is exemplified by our continued
support of centers of excellence that evaluate and present long-term data,"
said James McGlone, CEO and President of ONCURA.
[Back]
Online
tool estimates long-term chance of surviving prostate cancer -(Yahoo News-13/04/2004)
A study just completed
by researchers at the Josephine Ford Cancer Center has resulted in the
most comprehensive long-term prostate cancer survival model available
to date. An interactive version of the survival model is available online
at prostatecalculator.org. Patients and doctors who visit the site can
obtain a personalized 10-year survival estimate based on age, race, a
few clinical measures, and the kind of treatment being pursued. Once data
have been entered, a simple mouse-click provides the prognosis.
Dr. Ashutosh Tewari,
with the Josephine Ford Cancer Center (Detroit, MI) worked with investigators
at ANNs in CaP (Denver, CO) to retrospectively identify a cohort of 1,611
patients with clinically localized prostate cancer as well as 4,538 age,
race, and co-morbidity (those with additional diseases) matched controls.Based
on demographic and clinical variables, propensity risk scoring was used
to develop survival probability estimates for both patients and controls.
Because the calculator, and the companion look-up tables published in
the April issue of the Journal of Urology, provide a comparison with men
with similar characteristics but who do not have prostate cancer, users
receive a realistic estimate of the impact of prostate cancer on long-term
survival.
Prostate cancer is
the most common solid-organ male malignancy diagnosed in the United States,
with an estimated 189,000 new cases each year. Currently, African-American
men have the highest incidence of prostate cancer in the world (137 per
100,000 per year), and are 2.5 times as likely to die as whites. While
the reason for this is not known, some research suggests that black men
are often diagnosed at later disease stages. Dr. Tewari adds, "Our research
indicates that African-American men also tend to undergo less aggressive
treatment than whites, and additional studies by our group suggest that
if they received the same treatments, their prostate cancer survival rates
would be much closer to those of whites." The study also showed that a
man's level of co-morbidities can have as much or more of an impact on
his chances of long-term survival than his prostate cancer alone.
This new prostate
cancer survival model is the most comprehensive to date because it provides
an estimate of the likelihood of survival taking into account a patient's
age, race, comorbities, and treatment type. According to Dr. Tewari, "While
the study was not a randomized controlled trial comparing surgery, radiation
therapy, and watchful waiting, the method we used has been shown to eliminate
much of the bias introduced with a non-randomized study design. And the
inclusion of a large, matched control group is a great strength of our
study." While the study, which was awarded a first prize by the American
Urological Association, adds to the knowledge of how co-morbidities and
race affect the long-term survival of men with prostate cancer, an additional
benefit is that it prompted Dr. Tewari's team to ask and seek answers
to new questions: Why do black men receive less aggressive treatment than
whites? Are black men choosing less aggressive treatment themselves or
are their doctors suggesting the treatment? And, finally, is it worthwhile
for men with additional diseases to treat their prostate cancer? No personal
information is collected and patient privacy is respected. The site does
not promote particular doctors or specific treatments.
[Back]
Prostate
Cancer Surgery Helps with Urination-(Reuters Health-22/04/2004)
Men with localized
prostate cancer have a number of treatment options, all with pros and
cons. On the plus side for surgical removal of the prostate gland, the
procedure can also help some men urinate better, new research indicates.
In contrast, other treatments, such as radiation therapy, may actually
make urination worse. In agreement with a report released earlier this
month, the current findings suggest that when treatments are equally effective
in terms of survival, quality-of-life issues become paramount in selecting
one prostate cancer therapy over another. The current results are based
on a study of 50 men with urination problems who were later found to have
prostate cancer. All of the patients underwent radical prostatectomy,
as the surgical procedure is called. A variety of measures were used to
evaluate urinary function before and after surgery.
Dr. V. Kumar, from
the Royal Hallamshire Hospital in Sheffield, UK, and colleagues found
that for men with moderate to severe urinary symptoms, surgery resulted
in significant improvements in the strength of the urine stream and in
the ability to empty the bladder. These men also reported an improvement
in their quality of life. On the other hand, surgery did not improve urination
in men with mild symptoms, the team reports in the medical journal BJU
International. Six months after the procedure, 39 men had essentially
normal urinary function, 10 had mild leakage, but required no pads, and
1 patient required pads during heavy physical exertion. "This study confirms
that radical prostatectomy provides major benefits beyond cancer control
in men with pre-existing bothersome lower urinary tract symptoms," the
authors state. "This is important in counseling patients about treatment
options for clinically localized prostate cancer."
[Back]
Vegetable
Fiber Tied to Lower Prostate Cancer Risk-(Reuters Health-14/04/2004)
Men who eat their
veggies may be less likely than others to develop prostate cancer, a new
study suggests. Among more than 1,700 men with and without prostate cancer,
those who ate the most fiber -- particularly from vegetable sources --
had a lower risk of developing the disease, Italian researchers found.
The benefit was "moderate," they report in the International Journal of
Cancer, but the findings suggest that at least some forms of fiber offer
prostate cancer protection. A number of studies have suggested that eating
plenty of fruits and vegetables may help ward off prostate cancer, while
"Western"-style diets heavy in animal fat and dairy products may increase
a man's risk of the disease.
But not all studies
have reached these conclusions, and the importance of diet in prostate
cancer risk is still unclear. There is evidence that fiber-rich foods
may lower the risk of heart disease, diabetes and possibly certain cancers.
However, studies looking at fiber and prostate cancer have generally yielded
"null" findings, said Dr. Claudio Pelucchi, a researcher at the Mario
Negri Institute for Pharmacological Research in Milan and lead author
of the new study. The difference in his team's study, Pelucchi told Reuters
Health, is that it broke down men's fiber intake according to the type
and source of fiber. Fiber comes in two main forms, soluble and insoluble.
Soluble fiber partially dissolves in water, and its food sources include
vegetables, fruit, oatmeal and legumes. Insoluble fiber, which passes
through the digestive system largely intact, is found in foods like whole
grains, seeds and the skin on fruit.
For the study, Pelucchi
and his colleagues surveyed 1,745 men between the ages of 46 and 74 about
their diet and lifestyle habits. All of the men were surveyed while being
treated in Milan-area hospitals between 1991 and 2002; nearly 1,300 had
prostate cancer, while the rest were treated for conditions unrelated
to cancer. Those with prostate cancer were asked about their eating habits
during the two years before being diagnosed. Pelucchi's team found that
men with the highest overall fiber intake had a slightly lower risk of
prostate cancer than men with the lowest intake. When the researchers
looked at specific types of fiber, vegetable fiber emerged as most protective.
Men who got the most fiber from vegetables were 18 percent less likely
than those who ate the least to develop prostate cancer. Fiber from fruit
or grain products, specifically, was not related to a lower prostate cancer
risk, but soluble fiber did appear to protect against the disease. Pelucchi
pointed out that because vegetables and fruit were the chief sources of
soluble fiber, it's possible that the fiber, per se, did not bestow the
benefit. Other nutrients found in produce -- or the generally healthy
diet and lifestyle of fiber enthusiasts -- could be at work, he said.
[Back]
Paclitaxel
Carboplatin Combination Therapy Might Be as Effective as Mitoxantrone
Alone for Patients With Hormone-Refractory Prostate Cancer-(AACR Meeting-01/04/2004)
Preliminary results
of a phase 2 study suggest that a paclitaxel plus carboplatin combination
may be as effective as mitoxantrone alone for patients with hormone refractory
prostate cancer, researchers reported in a poster session here at the
American Association for Cancer Research 95th Annual Meeting. "The major
finding of our study is that hormone resistant prostate cancer must not
be considered any more as chemoresistant," said presenter Philippe Chollet,
MD, Centre Jean Perrin, Clermont-Ferrand, France. "Taxol carboplatin is
a good and effective combination as mitoxantrone alone is. In addition,
prostate cancer must be treated in the same way as breast cancer."
[Back]
Men
Take Note of Prostate Cancer in Family-(Reuters Health-13/04/2004)
Most men with a family
history of prostate cancer are well aware that they are at increased risk
of developing the disease themselves, new research indicates. Prostate
cancer is the most common cancer in U.S. men, and it is the second leading
cause of cancer death in men after lung cancer. Very little is known about
what causes prostate cancer, but a family history of the disease has been
shown to increase a man's risk. In fact, about 42 percent of all cases
of prostate cancer are thought to be hereditary. A team led by Dr. Jennifer
L. Beebe-Dimmer of the University of Michigan at Ann Arbor set out to
see whether relatives of men with prostate cancer were aware of their
increased risk. The study included 111 men who had a brother who had been
diagnosed with prostate cancer. The men were interviewed by telephone
to see how they perceived their risk of developing prostate cancer during
the next 10 years and during their lifetime. Most brothers of men with
prostate cancer accurately predicted that they were at increased risk
of cancer, the team reports in the April 1 issue of the journal Cancer.
Beebe-Dimmer explained
to Reuters Health that about one out of every six men in the general population
will be diagnosed with prostate cancer at some point in their lifetime.
"However, if a man has a brother, father or son diagnosed with prostate
cancer, his chances of being diagnosed are approximately one in two,"
she said. The majority of men in the study believed that they had at least
a 50-50 chance of developing prostate cancer. Although most men were aware
of their increased risk, younger brothers of men with cancer were more
concerned than older brothers. This is a "particularly interesting" finding,
according to the researchers, as the risk of prostate cancer increases
with age. Older brothers may be less concerned because they mistakenly
believe that they have passed the time of their greatest risk of cancer,
according to the report. Another possible explanation, according to the
researchers, is that older men may be less concerned because they assume
that they will not die of prostate cancer. This may be true, as most men
diagnosed with prostate cancer after age 70 end up dying of causes other
than prostate cancer.
The study also found
that men with two or more close relatives were more concerned about their
risk than men with a single affected relative. The investigators discovered
that men who were concerned about developing prostate cancer, particularly
in the short term, were more likely than other men to use alternative
medicine, such as supplements and vitamins, to try to reduce their risk.
Supplements have not been proven to prevent prostate cancer and may interfere
with some medications. But the findings show that men who are at high
risk of developing prostate cancer are seeking ways to reduce their risk,
according to the researchers.
[Back]
Study
suggests daily dose of aspirin may cut risk of prostate cancer-(Yahoo
News-11/04/2004)
Though the
evidence for it isn't as compelling as it is for some other cancers, aspirin
may modestly reduce the risk that a man will develop prostate cancer,
a large new study suggests. Men who regularly took aspirin had a 15 percent
lower risk of developing prostate cancer than non-users, and those who
took two or more pills a day had 20 percent less risk, the study found.
That's a relatively small reduction - experts usually like to see risk
cut in half to declare something substantially beneficial - but it's large
when considering the burden of disease. About 230,000 new cases of prostate
cancer are expected to be diagnosed in the United States this year. In
Wisconsin, where 4,500 new cases are projected, a 20 percent reduction
"would be almost 1,000 men who wouldn't get prostate cancer - a huge impact,"
said Douglas Reding, a Marshfield Clinic cancer expert who helped conduct
the nationwide study.
Looked at another
way, the benefit that this study suggests from aspirin use isn't much
less than the 25 percent reduction in risk that another study last year
found for men taking finasteride, sold as Proscar. Those findings, which
came from a more rigorously conducted study than the aspirin one, excited
federal health officials so much that they stopped the study and declared
the drug beneficial. Aspirin is a non-steroidal anti-inflammatory drug,
or NSAID, a category that includes most over-the-counter pain medications
except for acetaminophen (Tylenol). NSAIDs block a substance called COX-2,
which triggers inflammation and is thought to play multiple roles in cancer's
formation and spread. Many studies suggest that aspirin can prevent colon
cancer, but tests of it against hormone-fueled cancers such as breast
and prostate have been mixed. The most recent research gives reason for
optimism.
Last year, the Women's
Health Initiative study found that aspirin cut breast cancer risk by 20
percent to 30 percent, and earlier this year, a pooled analysis of results
on prostate cancer experiments concluded that aspirin might help. The
newest study adds to that notion. Results were presented at a recent meeting
of the American Association for Cancer Research in Orlando. The study
involved 30,000 men ages 55 to 74 in the Prostate, Lung, Colorectal and
Ovarian Cancer Screening Trial, a National Cancer Institute-funded experiment
under way at 10 sites around the country. About one-third of the men said
they took aspirin daily, although information on whether they took adult-
or baby-strength aspirin wasn't collected. After an average of four years
of follow-up, 1,338 prostate cancers were diagnosed in the group. The
cancer risk was 15 percent lower among men who took one aspirin a day
compared with those who took no aspirin, and 20 percent lower among those
who took two pills or more a day, said Lori Sakoda, a cancer institute
scientist who led the research.
So why not just recommend
aspirin? Because the drug carries risks, such as bleeding ulcers or intracranial
hemorrhage, and these risks rise with age, experts say. "Whenever you
have solid evidence that a drug has harm, you need equally solid evidence
of benefit," said Michael Thun, chief epidemiologist for the American
Cancer Society. "We're getting close with colon cancer," but more research
needs to be done before aspirin could be recommended for preventing other
cancers, he said. Even if aspirin turns out to be of only modest benefit
for the average man, it may be more beneficial for those at higher-than-average
risk, said Edward Giovannucci, a Harvard School of Public Health epidemiologist
familiar with the new study. "It might be more important for men with
a strong family history or high PSA tests," he said.
More research needs
to be done on which drug, what dose, at what age, and for how long various
NSAIDs or newer COX-2-inhibiting drugs should be taken, if at all. Each
person's risk profile for an array of diseases would need to be considered,
experts say. "One doesn't design preventive treatment only for one disease.
You really do things for overall health, so it's going to be the net benefit
compared to the net risk," Thun said. "For most people, heart disease
is going to drive this decision," he said, noting that many people already
use aspirin for this reason. Patrick Remington, an epidemiologist and
associate director of the University of Wisconsin Comprehensive Cancer
Center, said it was interesting that research increasingly suggests NSAIDs
may affect the risk of multiple cancers, not just one type. "It's beginning
to tell us something about how these tumors evolve. It seems that inflammation
is a fundamental process in the development of cancer," he said. "Ten
years ago, this information wasn't known."
[Back]
Fewer
Blacks, Latinos Treated for Prostate Cancer-(Reuters Health-08/04/2004)
Black men in the United
States are more likely to die of prostate cancer than are white men, and
new research suggests this disparity may stem from differences in how
the groups are treated for the disease. After reviewing the records of
more than 140,000 men diagnosed with prostate cancer, researchers found
that black and Latino men were less likely to undergo surgery or radiation
than were whites. As prostate tumors became more aggressive--more likely
to spread to other parts of the body--black and Latino men became less
and less likely to receive surgery or radiation compared with whites.
"As you increase the aggressiveness of the cancer, the disparity widens.
Which doesn't make sense," lead study author Dr. Willie Underwood told
Reuters Health.
Although some researchers
believe that black men may have genetic differences that make their cancers
more deadly, this report suggests that access to treatment may also be
responsible for the survival gap between blacks and whites diagnosed with
prostate cancer, co-author Dr. John Wei explained. Any number of factors
may affect whether black men receive surgery or radiation for prostate
cancer, Wei told Reuters Health. For instance, blacks may carry cultural
beliefs that cause them to forgo treatment, they may have less information
about its benefits, or may be treated differently by health staff, he
said. Underwood added that while there may be biological differences in
the prostate cancers of men in different racial groups, previous research
has shown that when blacks receive the same treatment as whites, they
are just as likely to survive prostate cancer.How
can we say that biology is the reason blacks and whites fare differently
with prostate cancer? he asked. "They've never had the same treatment."
Underwood and Wei,
both based at the University of Michigan in Ann Arbor, reviewed data collected
from 142,340 white, black and Latino men diagnosed between 1992 and 1999
with prostate cancer that had not yet spread. The authors noted who received
surgery or radiation for their cancer. Although black and Latino men were
less likely to be treated for prostate cancer than were whites, that gap
appeared to decrease during the 1990s, particularly among Latino men,
according to the Journal of Urology report. Underwood suggests that this
trend may stem from increased awareness of the benefits of treatment for
prostate cancer, which may have had more of an effect on Latino men.
[Back]
Prostate
Cancer Therapy Not Tied to Colon Cancer-(Reuters Health-29/03/2004)
There does not appear
to be an increased risk of colon cancer after prostate cancer, regardless
of how the prostate cancer is treated, according to findings presented
at the annual meeting of the American Association for Cancer Research.
Recently, an Australian study tied colon cancer to an increased risk for
prostate cancer, lead researcher Dr. Vinay K. Katukuri from Wayne State
University in Detroit, Michigan noted in an interview with Reuters Health.
However, it was unclear if the association also went the other way. One
area of concern has been the treatment used for prostate cancer. Specifically,
radiation therapy, a common treatment for prostate cancer, has been implicated
in the development of colon cancer. To investigate, the researchers tested
34 samples from colonic washings for early evidence of cancer in cells
from the colon. The samples came from 12 patients with prostate cancer
treated with radiation, 12 similar patients not given radiation, and 10
high-risk patients without colon or prostate cancer. According to Katukuri,
the groups did not differ significantly in their test results, suggesting
that all three were at equal risk for colon cancer. This study is "reassuring,"
he said, in that it suggests that radiation for prostate cancer is unlikely
to cause colon cancer. However, large forward-looking studies are needed
to confirm this, he added.
[Back]
Aspirin
May Help Prevent Prostate Cancer-(ET-12/02/2004)
Taking an aspirin
each day might be good for your heart, but new research suggests that
it may also reduce the risk of prostate cancer. Prostate cancer is the
most commonly diagnosed non-skin cancer in the U.S. and Canada, "and is
second only to lung cancer in terms of number of deaths it causes," Dr.
Salaheddin Mahmud from McGill University, Montreal, told Reuters Health.
"So it is very unfortunate that at the moment we do not know of any modifiable
risk factors for the development of this disease."
Previous reports
investigating the anti-cancer effects of aspirin and other non-steroidal
anti-inflammatory drugs (NSAIDs) have yielded conflicting results. For
this reason, Mahmud's team analyzed combined data from 12 reports to clarify
the effect of these drugs on the risk of prostate cancer. The results
are reported in the British Journal of Cancer. The use of aspirin was
associated with a 30 percent reduction in the risk of advanced prostate
cancer and a 10 percent reduction in total prostate cancer risk, the authors
note. "NSAIDs (and aspirin in particular) appear to offer some protective
effect against prostate cancer both in laboratory studies and in observational
studies in humans," Mahmud said. The study cited by the investigators
as "best equipped to address this issue" reported a strong anti-cancer
effect for aspirin use, but only among participants that had taken aspirin
for at least 4 years.
"It is too early
to recommend regular use of aspirin for prostate cancer prevention, but
the time is right" for forward-looking studies specifically designed to
address this topic, he added. Recently, two large randomized controlled
trials were begun to evaluate the protective effects of two of the newer
NSAIDs-Celebrex and Vioxx-Mahmud added. "I am not aware of any...trials
on the cheaper and more widely available" older NSAIDs, including aspirin.
The focus on the newer NSAIDs is partially because they have fewer side
effects, such as stomach bleeding, and partially because they are more
economically rewarding to drug companies, he said
[Back]
Nicholas
Piramal takes cancer drug to clinical trial stage-(Times of India-27/11/2003)
Nicholas Piramal
India Ltd (NPIL) plans to begin clinical trials on its new anti-cancer
drug by next year. The company's lead molecule has already undergone extensive
pre-clinical trials. The compound, NP102, a semi-synthetic category arrests
the abnormal multiplication of cells, which leads to cancer. In pre-clinical
tests conducted on mice at NPIL's research and development centre, it
has been found that the compound arrests multiplication of tumours in
prostate and leukaemia cases. It has also undergone some pre-clinical
tests in Germany and the US. The trials will now be conducted at WellQuest,
NPIL's contract research organisation (CRO) in Mumbai which recently received
approval from the Brazilian regulatory authorities. Swati Piramal said
"Maharashtra may soon become a hub for clinical trials in the world, with
its vast infrastructure in the public health sector and more than one
lakh patients visiting civic hospitals on a daily basis."
[Back]
U.S.
Agent Orange Study Finds Raised Cancer Risks-(Reuters-22/01/2004)
Air Force
veterans exposed to Agent Orange during the Vietnam War have a higher-than-average
risk of prostate and skin cancer, military researchers reported. The ongoing
study of 2,000 Vietnam veterans shows for the first time an elevated risk
of melanoma, the deadliest form of skin cancer. Previous studies have
found increased risks of prostate cancer, chronic lymphocytic leukemia
and also diabetes. "A new analysis of cancer incidence among Air Force
veterans of the Vietnam War found increased risks of prostate cancer and
melanoma in those who sprayed Agent Orange and other herbicides," the
Air Force Surgeon General's office said in a statement. It does not find
the veterans are any more likely to die of these cancers than the general
population. "It's just because we have new numbers, new exams," a spokesman
said. "The guys are getting older, so we are seeing higher incidences."
Between 1962 and
1971 an estimated 20 million gallons of herbicides, including Agent Orange,
were used to strip Vietnam's thick forests to make bombing easier. Veterans
exposed to the powerful pesticides have complained for years about a variety
of health problems, and in the late 1970s the government started to investigate
them systematically. The latest study, to be published next month in the
Journal of Occupational and Environmental Medicine, is not the last word
on cancer and Agent Orange, the Surgeon General's office warned. It has
many weaknesses and must be studied along with other research. For this
particular study veterans called the Ranch Hand group are being examined
regularly. Operation Ranch Hand was the unit responsible for the aerial
spraying of herbicides and medical experts say they got the highest exposure
to Agent Orange, which contains dioxins and other toxic chemicals. Starting
in 1986, their blood was tested for dioxin, a chemical that builds up
in the body and that can cause cancer and birth defects. "The dioxin determinations
were accurate but were measured 15 to 30 years after service in the Ranch
Hand unit," the surgeon general's statement said. "The study interpretations
are limited because other environmental exposures were not measured."
[Back]
Fruit
Nutrient May Fight Resistant Prostate Cancer-(Reuters Health-18/12/2003)
Men with prostate
cancer who have not responded to conventional treatments may benefit from
supplements containing a modified form of a fruit ingredient, preliminary
research suggests. After 13 men with prostate cancer that did not respond
to conventional treatment tried supplements containing modified fruit
pectin (MCP) for 12 months, 7 of the 10 men who completed the study showed
signs that their tumors were becoming less aggressive. The study was sponsored
by EcoNugenics, the company that sells the MCP supplements used in the
current research. All of the men underwent previous treatment for their
tumors, including surgery and radiation, after which they had all experienced
an increase in prostate specific antigen (PSA) in their blood, a sign
their cancer was continuing to grow. Three of the patients did not complete
the full course of treatment with MCP due to mild abdominal cramps or
diarrhea, which resolved after they stopped the treatment.
In an interview,
study author Brad Guess said that the results are too preliminary to warrant
recommending MCP to all men with prostate cancer. However, the findings
show that, for men with recurrent cancer who can handle the side effects,
MCP may help, he noted. "It may have some benefit as a relatively non-toxic
agent in a select group of guys with a rising PSA," Guess, a physician's
assistant at Prostate Oncology Specialist in California, told Reuters
Health. He added that pectin naturally occurs in the peel of citrus fruit,
and is generally not absorbed by the bloodstream. So eating large quantities
of fruit likely won't bring about the same benefit as taking a supplement,
which contains pectin that is modified so that it is absorbed in the bloodstream,
he said.
During the study,
reported in the journal Prostate Cancer and Prostatic Diseases, Guess
and his team asked 13 men with prostate cancer to take six capsules of
MCP three times per day for one year, for a total daily dose of 14.4 grams.
Among the 10 patients who completed the study, seven experienced a slower
rise in blood levels of PSA, a sign that their tumors were becoming less
aggressive. In an interview with Reuters Health, study co-author Dr. Stephen
Strum, an oncologist specializing in prostate cancer in Oregon, explained
that previous experiments have shown that MCP may block an important substance
that enables cancer to grow and spread. According to Strum, our immune
system is typically strong enough to fight off individual cancer cells.
To outwit our natural defenses, he said, cancer cells exhibit a protein
on their surfaces that enables them to combine together, forming a clump
large enough to become a threat to health. "The cohesiveness of the enemy
cells, the tumor cells, is an important factor for the cancer to grow
and spread," Strum explained. Recently, investigators discovered that
MCP blocks this surface protein, known as galectin-3, which may explain
why it helps men with prostate cancer, Strum noted. Guess added that MCP
may also work in people with other types of cancer, as well.
[Back]
Two
Drugs Better Than One for Enlarged Prostate- (HealthDayNews -17/12/2003)
Two drugs are better
than one when it comes to treating men with enlarged prostates. Doxazosin
and finasteride worked in concert to reduce severe complications from
the condition and the need for surgery, claims an article in the Dec.
18 issue of the New England Journal of Medicine. "This is a nice add-on,
but [the combination therapy] has certain intricacies that all must be
looked at," says Dr. Perinchery Narayan, director of the North Florida
Research Institute in Gainesville. Enlargement of the prostate affects
more than half of American men over the age of 50. The prostate is located
next to the urethra, which passes urine from the body, and the bladder.
When enlarged, it can pinch the urethra and disrupt the flow of urine.
In extreme cases, it can even cause "acute urinary retention," or the
inability to urinate.
Doctors routinely
prescribe one of two drugs for the condition: doxazosin, an alpha blocker,
and finasteride, which is also used to treat baldness. More serious complications
such as acute urinary retention may require surgery. "Both these drugs
have been used separately and individually for 10 years or more, in some
cases with good success, but indiscriminately," says study co-author Dr.
Claus G. Roehrborn, chairman of the department of urology at the University
of Texas Southwestern Medical Center in Dallas. "Doctors didn't make a
huge difference whether choosing one or the other." Because the two drugs
work by such different mechanisms, however, a combination approach "intuitively
made sense," Roehrborn adds.
Doxazosin essentially
relaxes the muscle at the opening of the bladder so urine can flow. "Alpha
blockers give symptom relief but don't change the natural progression
of the condition," explains Dr. Jed Kaminetsky, a clinical assistant professor
of urology at New York University School of Medicine. The other class
of drugs, called 5 alpha-reductase inhibitors, works by a hormonal mechanism
to shrink the prostate and ease the pressure on the urethra and bladder.
"These work very differently, so it should have made sense to use them
in combination to have a synergistic effect," Kaminetsky says. Two previous
studies looked at the combination but failed to show a benefit, probably
because they did not last long enough.
A previous study,
for which Narayan was an investigator, only followed patients on the combination
therapy for one year. "Since [enlarged prostate] is a long-term disease
that is progressive and occurs over many years, one year may be too short
a period of time," Narayan notes. The current study followed more than
3,000 men for about five years and is the largest study of its kind ever
conducted. Participants randomly received either doxazosin alone, finasteride
alone, a combination of the two or a placebo. Doxazosin reduced the risk
of overall progression of the condition by 39 percent and finasteride
by 34 percent. The combination therapy reduced this risk by 66 percent.
Finasteride and the combination therapy reduced the risk of acute urinary
retention and the need for surgery.Doxazosin,
by contrast, did not have an effect in these areas. About 10 percent of
the men taking finasteride experienced side effects in sexual function.
Doxazosin users sometimes experienced dizziness, low blood pressure and
fatigue.
Regardless of the
positive results, treatment is not likely to led to a straightforward
switch to combination therapy. For one thing, a trial earlier this year
found that while finasteride reduced the risk of some types of prostate
cancer, it also increased the risk of other cancers. "Nobody expected
these kinds of results with the prostate cancer prevention trial," Narayan
says. "This complicates the picture." Roehrborn thinks men at high-risk
for progression could be started on both drugs at once, while low-risk
patients could take one or the other. A person's risk is determined by
looking at prostate volume and PSA (prostate-specific antigen) level.
Also, an enlarged prostate is a complicated condition. Sometimes a prostate
large in size is less troublesome than a smaller one. For this reason,
finasteride wouldn't make any sense for a man with a small prostate, Kaminetsky
says.
[Back]
Obesity
Linked to Prostate Cancer Aggressiveness-(Reuters Health-23/12/2003)
Obesity increases
the risk for higher grade prostate cancer and higher recurrence rates
after radical prostatectomy, two research groups report. Both propose
that obesity may at least partially explain the racial disparity in prostate
cancer outcomes. Epidemiologic studies have been inconsistent in showing
a relationship between obesity and prostate cancer, the two teams note
in a December 22 online release from the Journal of Clinical Oncology.
In fact, obesity seems to be a stronger risk factor for prostate cancer
mortality than incidence.
Dr. Christopher L.
Amling, at the Naval Medical Center in San Diego, and colleagues evaluated
data for 3162 patients who underwent radical prostatectomy between 1987
and 2002, as documented in the Center for Prostate Disease Research database.
Nineteen percent of the cohort was obese, as defined by a body mass index
of 30 kg/m or above. Obesity was associated with a median PSA of 6.3 versus
6.1 in the non-obese group (p = 0.027), higher Gleason score (p = 0.003),
incidence of positive surgical margins (p = 0.007), and biochemical recurrence
rate (p = 0.027). Compared with white men, black men presented with cancer
at younger age and with tumors of higher grade and stage. They were also
significantly more obese. In
multivariate analysis, black race but not BMI remained a significant independent
indicator of cancer recurrence.
Meanwhile, the Shared
Equal Access Regional Cancer Hospital (SEARCH) database Study Group, led
by Dr. Stephen J. Freedland at Johns Hopkins School of Medicine in Baltimore,
also reports that black men had significantly higher mean BMI than white
men. Included in the analysis were 1752 patients treated with radical
prostatectomy between 1988 and 2002. Of note, the incidence of obesity
approximately doubled over the last decade of the study. Obese patients
were younger and had higher biopsy and pathologic Gleason scores, Dr.
Freedland and associates report. The risk for PSA failure was significantly
increased for those with BMI of 35 kg/m (p = 0.002). Multivariate analysis
showed that obesity, but not race, was independently associated with disease
recurrence. "Given the disproportionate burden of on black men, programs
targeted to control obesity in the black community may be warranted,"
they suggest.
In an editorial,
Dr. Alfred I. Neugut and colleagues at Columbia University in New York
note that obesity, while not a consistent risk factor for prostate cancer
incidence, is consistently associated with prostate cancer mortality.
"In light of the increasing worldwide incidence of obesity, the identification
of obesity as a risk factor for aggressive prostate cancer is important
because it may be one of the few modifiable risk factors for prostate
cancer," they maintain.
[Back]
Earlier
Cancer Screening Supported for Black Men-(Reuters Health-29/12/2003)
In 1997, the American
Cancer Society recommended early prostate cancer screening for certain
high-risk groups, including black men. Now, new research indicates that
since those recommendations were made, differences between black and white
men in prostate cancer detection have narrowed. Based on initial blood
levels of PSA, a prostate cancer marker, black men are now being diagnosed
at an earlier disease stage than they use to be. This is good news because
earlier diagnosis can mean earlier treatment and, as a result, better
outcomes.
The findings, which
are reported in the International Journal of Radiation Oncology Biology
Physics, are based on a study of 2332 men with prostate cancer who were
seen at a university hospital or its community affiliates between 1990
and 2001. Of these patients, 1968 were white and 364 were black. From
1990 to 1996, the average initial PSA for black patients was 14.6, much
higher than the value of 10.5 for whites, lead author Dr. Charlie C. Pan
and colleagues, from the University of Michigan at Ann Arbor, report.
In the period after the ACS guidelines were published, the racial difference
in initial PSA, although still present, was less pronounced. This was
due to a 3.8-point fall in the initial PSA for blacks that outpaced the
1.0 drop seen in whites. During both time periods, blacks were diagnosed
at a younger age than whites. Over the study period, disease severity
at the initial diagnosis improved regardless of race, the authors note.
"The overall decline in initial PSA levels in both racial groups is good
news as it shows that patients have become more aware of the disease and
are coming to us when their cancer is most treatable," Pan said in a statement.
"The racial differences in initial PSA levels observed in the study prove
that African-American men are susceptible at an earlier age to this disease
and should continue to be screened at a younger age than Caucasians, as
recommended by the ACS," he added.
[Back]
Value
of Prostate Blood Test Examined-(AP-28/12/2003)
Millions of dollars
are spent annually to monitor prostate health in men over 75 even though
research shows little benefit in screening such men for prostate cancer,
a study says. "There is no evidence that screening men of this age would
be beneficial to them, so this may not be the best use of health care
resources," said Dr. Siu-Long Yao, a genital-urinary oncologist at the
Cancer Institute of New Jersey in New Brunswick, N.J. He was senior author
of the study appearing this week in the Journal of the National Cancer
Institute. "If you take all elderly men who die and do an autopsy, 30
to 70 percent will have prostate cancer, but they died of something else,"
said Yao. "Diagnosing the prostate cancer may lead to unnecessary complications
in elderly patients who are more likely to die of something else, such
as cardiovascular disease."
However, Dr. Richard
G. Middleton, chairman of urology at the University of Utah Medical School
and a contributor to the prostate cancer guidelines for the American Urological
Association, said the study was "too simplistic." "A routine PSA (Prostate
Specific Antigen test) in a man over 75 would ordinarily not be necessary,"
but the blood test would be useful for a man with a history of prostate
problems, he said. "There are many situations where the PSAs are helpful
in monitoring and following an elderly man," said Middleton. "I object
to the idea that it was somehow bad form to order a PSA on an elderly
patient." Middleton said PSAs are needed to monitor for the recurrence
of tumors in elderly men who have had surgery or radiation for prostate
cancer earlier in life. PSAs also are appropriate, he said, for elderly
men who have a suspicious-looking prostate on examination, who have a
known tumor, or who have a previous history of an elevated PSA count.
In a survey of 7,889
men, researchers found that 32.5 percent of men over 75 received PSA blood
tests, an estimated 1.5 million men a year. Medicare typically pays $25.70
for the lab work, federal officials said, suggesting that more than $38
million is spent on those tests. The PSA test does not detect cancer directly.
Instead, it determines, in effect, if a patient has too much prostate
tissue. That excess tissue can be caused by inflammation, by enlargement
common to older men, or by cancer. A positive PSA test has to be followed
up with a biopsy or other procedures before cancer can be confirmed. "Most
patients with an elevated PSA do not have prostate cancer," said Yao.
And even if prostate cancer is first detected in a 75-year-old, the chances
are very high that the patient will die of some other disorder before
the slow-growing cancer could cause death, he said.
Yao said the study,
based on data extracted from the National Health Interview Survey, showed
that men over 75 are more likely to get a PSA test than a fecal occult
test, a screening test that detects symptoms of colon cancer. Studies
have shown that patients who get regular fecal occult tests tend to live
longer than those who don't, he said, but there is no such evidence for
a PSA test. "What we found surprising is that something (PSA) with little
proof of benefit was being used more commonly than tests (fecal occult)
that have 20 years of proof behind them," said Yao. Among the surveyed
elderly men, 88 percent said they got the PSA test at the suggestion of
their doctor, but only about 66 percent of those who got the test recall
a discussion with the doctor about the risks and benefits of the test.
For a test of questionable value, Yao said that virtually all the doctors
should have frank discussions with patients.
[Back]
White
Men Survive Prostate Cancer Longer-(AP-18/11/2003)
Black men do not
survive as long as white men after treatment for localized prostate cancer,
according to a new study. Researchers at the University of North Carolina
at Chapel Hill analyzed the records of 5,747 black men and 38,242 white
men who had been treated for prostate cancer that had not spread. They
found that the median survival time for black men was 1.7 years less than
the survival time for white men. The difference was even greater, 1.8
years, for patients who received surgery. Black prostate surgery patients
lived an average of 10.8 years, while white patients lived 12.6 years.
For patients of either
race who received radiation treatment, however, the differences in median
survival was not significant, the researchers report. Specialized radiation
therapy is the preferred treatment for locally advanced prostate cancer,
but black patients may have less access to this therapy, the researchers
said. There may also be biologic factors that affect the way black men
and white men react to prostate cancer treatment, the study suggested.
"Researchers should continue to investigate racial disparities in treatment
outcomes as well as the specific social, biologic or environmental conditions
that may be responsible for these disparities," the researchers conclude
in the study. Dr. Paul A. Godley of the Lineberger Comprehensive Cancer
Center at the University of North Carolina was head of a team that conducted
the research.
[Back]
Prostate
Cancer 'Seed' Treatment More Common-(Reuters Health-14/11/2003)
In the U.S., more
and more men with prostate cancer are receiving a form of treatment called
brachytherapy, new research suggests. Brachytherapy involves the placement
of tiny radioactive "seeds" into the prostate gland that destroy the tumor.
Brachytherapy is thought to deliver the radiation more precisely than
giving it externally with a machine, known as external beam radiotherapy.
In 1994, 5 percent of men with early prostate cancer received brachytherapy.
In just 5 years, however, this percentage jumped dramatically to 36 percent,
according to the report in the medical journal Cancer. In the Patterns
of Care Study (PCS) for 1999, Dr. W. Robert Lee, from Wake Forest University
in Winston-Salem, North Carolina, and colleagues assessed the use of radiation
therapy in more than 36,000 men with early prostate cancer.
"The current report
is the first PCS to describe in detail the processes involved with prostate
brachytherapy in the management of (early) prostate cancer," the researchers
note. More than a third of patients were treated with brachytherapy. However,
it was often not the sole method used--nearly half of brachytherapy patients
also received external beam radiotherapy, the authors note. Compared with
men who only received external beam radiotherapy, brachytherapy patients
were younger and had less severe cancers, the researchers state. The results
indicate that brachytherapy utilization has increased markedly in recent
years. "It will be interesting to examine whether this large shift in
practice patterns will result in improved outcomes for patients," the
investigators state.
[Back]
UT
Southwestern Researchers Learn Certain Enzyme Inhibitors May Help in Cancer
Therapy Following Initial Procedures-(ET-23/10/2003)
Certain enzyme inhibitors
may slow tumor formation within weeks and could lead to treatments that
retard or prevent recurrences of cancers, researchers at UT Southwestern
Medical Center at Dallas have discovered. Their findings appear in the
Septemebr 2003 issue of the journal Cancer Research. The researchers sought
to inhibit telomerase, an enzyme that maintains telomeres - repeating
sequences of DNA at the end of each chromosome that are believed to function
as a counting mechanism for cellular aging. Telomerase prevents the shortening
of the sequences of DNA that occurs in normal cells as they age. The enzyme
is found in most types of tumor cells but not healthy cells, indicating
telomerase inhibitors may be a powerful new approach to chemotherapy.
Telomerase inhibition, however, has posed challenges for therapy.
In earlier studies,
scientists have found that months of treatment with an inhibitor are required
before tumor growth could be expected to significantly slow. The UT Southwestern
researchers treated cultured human tumor cells with a unique compound
that blocks telomerase activity, and the cell proliferation slowed substantially
after just a few weeks. Further, prostate cancer cells treated with the
inhibitor barely formed tumors in mice and yielded very low levels of
prostate specific antigen (PSA), a marker associated with malignancy.
Cells treated with a similar compound that was not a telomerase inhibitor
formed large tumors with high PSA levels. "Telomerase is widely appreciated
as a promising target for therapy," said Dr. David Corey, professor of
pharmacology and biochemistry and the study's senior author. "Our results
suggest that if you can inhibit telomerase in tumor cells and shorten
telomeres, you will slow the growth of tumors." The researchers also discovered
that when the telomerase inhibitor is combined with standard cancer therapeutic
agents carboplatin and cisplatin, there are additional antiproliferative
effects.
Dr. Corey said these
results suggest a relatively small amount of telomere shortening is sufficient
to slow tumor growth, and telomerase inhibitors are a useful therapeutic
option, especially in combination with agents already being used to treat
patients. "No one is suggesting telomerase inhibitors alone would cure
cancer, but in conjunction with standard therapy, they might help to slow
or prevent the recurrence of tumors after the initial cancer has been
removed through surgery, radiation or chemotherapy," Dr. Corey said. "Since
most patients die from the recurrence of cancer, effective telomerase
inhibitors could have a large impact on the treatment of many different
types of cancer." A similar telomerase inhibitor currently is in advanced
preclinical trials with the Geron Corp. These new findings are likely
to influence how clinical trials are designed and interpreted and to provide
more support for pushing them forward, Dr. Corey said.
[Back]
Getting
a Better Prognosis for Prostate Cancer- (HealthDayNews -23/10/2003)
Doctors may be better
able to predict the fates of prostate cancer patients by changing the
location of biopsies they take to check for disease. New research finds
biopsy results from the side of the prostate with the most advanced tumors
are more closely linked to the chances of the cancer returning after treatment
than are biopsy results from all over the gland. "In the old days, we
used to say you had cancer and that was the general information you got,"
perhaps along with an analysis of how aggressive the cancer is, says the
study's co-author, Dr. Stephen Freedland, a clinical instructor at Johns
Hopkins University School of Medicine. "What studies like ours are saying
is it's no longer acceptable to [just] say that."
Prostate cancer is
the most commonly diagnosed cancer among American men and kills about
30,000 each year, according to the National Prostate Cancer Coalition.
Doctors can choose from a variety of treatments, but the side effects
can include incontinence and impotence, leading many patients to carefully
consider their choices. In the new study, released online this week and
appearing in the December issue of the journal Cancer, researchers examined
the medical records of 535 men who had prostate removal surgery from 1988-2002.
The researchers wanted to see how early biopsies predicted how the men
fared later. According to study co-author Dr. Christopher Kane, an associate
professor of urology at the University of California at San Francisco,
doctors typically take 10 biopsies from each prostate cancer patient by
sticking needles into the prostate and pulling out thin "cores." The process
is quick and painless because local anesthetic is given, Kane adds. If
cancer exists, pathologists can measure how advanced it is and how aggressive
the cells appear to be.
Prostates have two
lobes, and the researchers found the number of "positive" biopsies on
the side with the highest degree of cancer is a better predictor of future
problems than the number of positive biopsies as a whole. "The dominant
tumor tends to be driving patients' outcomes," Kane says. "It kind of
makes sense once you think about it." While doctors may not be able to
immediately use the biopsy information to help them decide which treatment
to try, it should give patients a better idea of their prognosis, Kane
says. It will also help doctors understand which patients face the highest
risk of recurrence and may belong in research trials, he adds.
Dr. Lester Klein,
a urologist at Scripps Clinic in San Diego, says more research needs to
be done before doctors will accept the results. At this point, the findings
are only "suggestive," he says. But the research is important because
doctors need more information when they consider options for prostate
cancer patients, he adds. "What we're trying to figure out is which patients
should be operated on and which shouldn't be operated on," he says. "There's
no use operating on something if it's going to fail." Radiation and surgery
remain the major treatments for prostate cancer, Klein says, and patients
make the final call. "Most guys want to see their grandchildren grow up,"
Klein says. "If there's a small chance of success, they'll take it."
[Back]
New
Marker for Prostate Cancer-(HealthDayNews-03/11/2003)
A cellular protein
called PCa-24 has been identified as a unique marker for prostate cancer.
The discovery of the protein, which will be published in the Dec. 15 issue
of Cancer, could lead to development of a screening test that clearly
distinguishes between prostate cancer and benign prostatic hyperplasia
(BPH) before doctors perform a biopsy. The research was led by Dr. Brian
Liu, an assistant professor of surgery and urology at Brigham and Women's
Hospital in Boston. He and his colleagues used proteomics -- the study
of all proteins produced by a cell -- to identify PCa-24, which is unique
to prostate cancer cells and is a smaller protein than prostate specific
antigen (PSA). In this study, PCa-24 was exclusively detected in 94 percent
of epithelial cells from prostate cancer but was not detected in normal
prostate cells or in BPH cells. "One possible application for our findings
is to determine the presence or absence of this protein in serum of patients
with prostate cancer versus those with other urologic diseases, including
BPH," the authors write.
Currently, screening
for prostate includes testing levels of PSA. Values of PSA greater than
4 can warrant further evaluation with a needle biopsy. But PSA can be
produced in high levels by either prostate cancer or BPH, which is a nonmalignant
disease that causes narrowing of the urethra and difficulty urinating.
Also, nearly 35 percent of men with prostate cancer have normal PSA values.
This means that measuring PSA serum level alone is not a specific marker
for prostate cancer and may result in unnecessary needle biopsies.
[Back]
Tomatoes
Offer 'Real' Cancer Aid-(Yahoo News-05/11/2003)
Tomatoes may help
prevent prostate cancer, but don't count on tomato pills. In research
on rats, scientists have found that supplements based on tomato extracts
may not work to prevent the disease the way the whole fruit does, researchers
reported yesterday. Research published in this week's issue of the Journal
of the National Cancer Institute suggests that men seeking to benefit
from the properties of tomatoes will have to eat tomato sauce, paste or
the whole fruit instead of popping a pill. "Our findings strongly suggest
that risks of poor dietary habits cannot be reversed simply by taking
a pill," said Dr. Steven Clinton of Ohio State University, who helped
lead the study.
Many studies have
found that men who eat tomato products have a lower risk of prostate cancer,
and scientists have credited lycopene, the compound that makes tomatoes
red. But other experts say whole foods contain a variety of compounds
that work together for healthful benefits. Teams at the University of
Illinois and Ohio State treated 194 male rats with a chemical that induces
prostate cancer and then gave some rats whole tomato powder, some pure
lycopene and the rest a standard diet with no supplements. Rats fed the
tomato powder diet were 26 percent less likely to die of prostate cancer
than rats not given any supplements, but rats given lycopene were only
slightly more likely to survive. Reuters
[Back]
Advanced
prostate cancer patients tested with high doses of vitamin D-(CP-07/11/2003)
The equivalent of
100 vitamin D pills weekly is being given to men across Canada suffering
from advanced prostate cancer to test the dosage's impact on chemotherapy.
The trials will be run at health centres in several Canadian cities as
part of a large research project begun in the United States last year.
"By giving high doses of vitamin D, the hypothesis is that (it) can help
make the chemotherapy kill the cancer cells better," Dr. Kim Chi of the
B.C. Cancer Agency said. The treatment is not viewed as a possible cure,
but researchers are hopeful it will improve patients' symptoms and prolong
their lives, said Chi, who is in charge of the Vancouver trials. Half
the patients involved in the study will be given a biologically active
form of vitamin D called calcitriol, while the other half will receive
a placebo. Patients will take the vitamin in pill form along with the
chemotherapy drug docetaxel. "I expect within the next year or two, we
will have an answer as to whether vitamin D really adds into the chemotherapy
effect."
He emphasized cancer
sufferers should not go out and consume large amounts of the vitamin by
themselves since high doses of the store-bought vitamin can be toxic.
"The equivalent would be like taking over 100 TAB Capsules of regular
vitamin D that you can buy," he said, adding he's known of cancer patients
who took high doses of vitamin C and "had side effects without telling
anybody." The Canadian trials will also be run in Calgary, Edmonton, Winnipeg,
Ottawa, Toronto, London, Montreal and Quebec City. The trial subjects'
special doses will be administered and scheduled in such a way that patients
won't experience toxic effects. Patients will receive their doses every
seven days for three weeks with one week off for rest. No side effects
have been reported by patients already involved in tests in the United
States, he said. "The vitamin D does not seem to add to any of the side
effects of the chemotherapy," said Chi.
One of the Vancouver
trial participants said he wasn't nervous about starting the tests. "I
guess I'm a little anticipatory," said Ted Ewing, 68, who was diagnosed
eight years ago. "Whether I get the vitamin D or not is depending on what
side of the line I'm on when they decide to make this treatment available,"
said Ewing. "It doesn't really matter," he figured. "The chemotherapy
is something that has to be done to have a little longer and a little
better lifestyle."
It's known that vitamin
D, the so-called sunshine vitamin, has "anti-prostate cancer activity,"
said Dr. Paul Rennie, director of laboratory research at the Prostate
Centre at Vancouver General Hospital. "Some of the observations concerning
vitamin D have come from farmers who have been shown to have a lower incidence
of prostate cancer than other occupations," said Rennie. "This is believed
to be the enhanced or increased exposure to sunshine coupled with the
activity of vitamin D." There is currently very little in the medicine
cabinet for prostate cancer sufferers not responding to hormonal therapy,
said Rennie. "When hormonal therapies fail, really physicians are grasping
for straws or anything they can use to fight the disease in the patient,"
he said. "All these new advances are extremely important." Prostate cancer
is the most common cancer in men and the second most deadly form of the
disease, according to the website of the Prostate Cancer Research Foundation
of Canada. The foundation says up to 19,000 Canadian men are diagnosed
each year.
[Back]
What
Makes Prostate Cancer Aggressive?-(HealthDayNews-06/11/2003)
A single tumor suppressor
gene isn't necessarily enough to protect against the progression of prostate
cancer, says a study by researchers at Memorial Sloan-Kettering Cancer
Center Previous research found one or both copies of something called
the PTEN tumor suppressor gene are lost in 70 percent of men with prostate
cancer at the time of diagnosis. But it's been believed the one remaining
copy of the PTEN gene, which controls cell proliferation, still protected
men against the spread of cancer. But in research with mice, the Sloan-Kettering
researchers found that alone may not be enough: It's the dose of PTEN
protein that determines whether the tumor becomes an aggressive cancer.
This finding could help scientists develop new ways to diagnose, treat
and possibly prevent prostate cancer. "We have shown that prostate cancer
development is not just affected by mutation and loss of the PTEN gene
but that its progression is dose-dependent on the PTEN protein, which
we have measured for the first time," senior author Dr. Pier Paolo Pandolfi,
head of the Molecular and Developmental Biology Laboratory at Memorial
Sloan-Kettering, says in a prepared statement. "Two men, each with one
PTEN gene left, could have totally different disease outcomes depending
on the actual dose of PTEN protein coming from that gene."
[Back]
High
Dairy Intake Linked to Testicular Cancer Risk-(Reuters Health-13/10/2003)
Canadian men who
consume comparatively high amounts of dairy products have an increased
risk of testicular cancer, according to a new study. Although testicular
cancer is a relatively rare lesion, accounting for only 1.1% of all malignant
neoplasms in males in Canada, it is the most common cancer among Canadian
men 20 to 45 years of age," Dr. Michael J. Garner, of the University of
Ottawa, Ontario, Canada, and others write in the International Journal
of Cancer.
The researchers obtained
dietary information from 601 patients with testicular cancer and 744 similar
men without cancer. They used a 69-item food-frequency questionnaire to
collect data on 17 food groups, 15 nutrients, and 4 individual foods.
Subjects who consumed high levels of dairy products had an increased risk
of testicular cancer. In particular, a high intake of cheese was tied
to an 87 percent higher likelihood of developing testicular cancer. Luncheon
meat intake was also associated significantly with testicular cancer risk
in the total sample, Garner's team found. The investigators report that
none of the nutrients were linked the risk of testicular cancer, but carbohydrate
intake was marginally associated with one type of testicular cancer. "Our
study adds significantly to the sparse literature on dietary risk factors
for testicular cancer," the researchers write. "Although the present study
provides evidence of increased risk in relation to the consumption of
dairy products, the role of diet in testicular cancer etiology requires
further research," they conclude.
[Back]
Study:
Gene Variation Raises Prostate Cancer Risk-(Reuters-14/10/2003)
Some men are more
likely to get prostate cancer because they have a particular genetic variation
that makes them more susceptible to environmental or hormonal factors
that can cause the disease, scientists said. Researchers in the United
States have discovered that men who develop the disease, which is one
of the most common male cancers, have variations in a gene called CYP1B1.
Mutations in the gene have already been implicated in smoking-related
bowel, breast, ovarian and head and neck cancers. Scientists at Wake Forest
University School of Medicine in North Carolina believe it is also linked
to prostate cancer and may provide new insights into what causes the disease
and how to prevent it. "Previous research suggests prostate cancer arises
in certain individuals due to a combination of genetic and environmental
factors. Our study suggests that the genetic make-up of some men leaves
them more susceptible to potential carcinogens in the environment or hormones
in the body that could trigger the disease," said Dr Jianfeng Xu, who
headed the research team.
Genetic and environmental
factors are thought to cause cancer. A genetic mutation makes a person
more susceptible to the disease, which can be triggered by an environmental
cause such as toxic chemicals. Scientists suspect CYP1B1 can prevent as
well as cause cancer. The gene helps the body rid itself of harmful chemicals
that can trigger the disease. But prostate cancer is a hormonal disease
and the gene may also activate the male hormone testosterone. Xu and his
colleagues and researchers at Johns Hopkins University in Baltimore who
collaborated on the study suspect that variations in the gene determine
whether it will work to prevent prostate cancer or to activate it. "This
study suggests men with a particular gene variant have an increased risk
of prostate cancer. It's an exciting finding because we know the gene
interacts with certain cancer-causing chemicals -- studying this more
closely will bring us closer to finding out what factors in the environment
or within the body may trigger the disease," Xu added.
The scientists pinpointed
the variations in the gene by studying more than 400 prostate cancer patients
and 220 healthy men. Their findings are reported in the British Journal
of Cancer. More than half of the cancer patients had a family history
of the disease. After looking at 13 variations in CYP1B1, they discovered
that one cluster of variations was more common in the men who had a family
history of the disease and another was more prominent in the healthy men.
Prostate cancer is among the six top cancer killers worldwide and the
incidence of the illness is rising in many countries. Most cases are diagnosed
in men 50 years and older. Early diagnosis and treatment can greatly improve
survival. Difficulty and pain urinating, blood in the urine and pain in
the back and hips are possible signs of the disease. Men with a family
history of the disease have a greater risk of suffering from prostate
cancer. A high fat diet may also increase of odds of developing the disease.
[Back]
Diagnocure
Set to Launch Prostate Cancer Test-(Reuters-22/09/2003)
Diagnocure Inc.,
which makes tests to diagnose cancers, said that U.S.-based Bostwick Laboratories
would start selling its test to detect a gene specific to prostate cancer
in urine. Diagnocure hopes to garner at least $1 million in revenue from
the sale of the test in the United States in the next year, Chief Executive
Pierre Desy told Reuters in an interview. "This is a first step for us
to significantly improve detection of prostate cancer," Desy said, adding
that Bostwick will market the ASR version, or a "home-brewed" form, of
the test starting Oct. 15. Desy said the test will be the first to use
gene-based detection to diagnose prostate cancer.
Until now, tests
to diagnose prostate cancer suffer from a lack of specificity. As a result,
only one in four patients who test positive is found to have prostate
cancer after a biopsy, Desy said. Bostwick, based in Richmond, Virginia,
is a private pathology laboratory and specializes in urological diseases.
It has a sales force of about 30 people, Desy said. Desy said Diagnocure
will also develop the test further and is now in discussions with an international
diagnostics company. Once a deal is reached, which could be within two
months, further clinical trials and research will form the basis for getting
the test approved by the U.S. Food and Drug Administration (news - web
sites). If all goes according to plan, the company could turn profitable
next year, he said.
[Back]
Study:
Prostate Cancer Death Rates Down-(AP-23/09/2003)
Earlier detection
and wide use of hormone treatment have driven death rates from prostate
cancer dramatically lower over the last 10 years in North America and
Western Europe, new research shows. Previous studies have demonstrated
hormone treatment delays the progression of prostate cancer and makes
patients feel better, but until now there has been little solid evidence
that the approach can save lives. Death rates from prostate cancer have
dropped by one-third in North America and by 20 percent in Europe since
1990 among men aged 65 to 74, according to Sir Richard Peto, who presented
findings analyzing evidence from 40 years of prostate cancer research.
Prostate cancer
kills more than 200,000 men annually worldwide. About 190,000 new cases
of prostate cancer are diagnosed in the United States every year, and
about 30,000 men died of the disease in 2002, according to American Cancer
Society statistics. Earlier detection and better surgery and radiotherapy
have helped reduce death rates. But Peto, a professor of medical statistics
at Oxford University who has conducted many of the key studies evaluating
cancer treatments and risks, said the lifesaving benefit of hormone treatment
has been vastly underrated. He reported the accumulated evidence from
several studies on hormone treatment involving a total of 5,000 men. Taken
separately, the studies were inconclusive, but analysis of them all together
showed that when doctors gave hormone treatment immediately instead of
waiting until the disease progressed, the risk of dying from the disease
within 10 years dropped by one-third. "This definitely shows that hormone
treatment works," said Dr. Michael Thun, chief of epidemiology at the
American Cancer Society. "There is still debate about how much of the
decline in (national) death rates is due to treatment and how much is
due to earlier detection through screening, but the evidence for the importance
of treatment in these declines is getting stronger," said Thun, who was
not involved in the research.
The findings follow
similar success reported in breast cancer, where death rates in middle
age have fallen by about one-third since 1990. Breast cancer, in most
cases, is driven by the female hormone estrogen, while prostate cancer
is most often driven by the male sex hormone, testosterone. Even after
successful surgery, a few cancer cells may remain undetected nearby or
in distant parts of the body. Radiation therapy can kill off cancer cells
near the tumor site. Undetectable cells that have traveled elsewhere in
the body can be attacked by chemotherapy in breast cancer, but not in
prostate cancer. Hormone therapy prevents the fragments from being stimulated
into becoming more dangerous by the body's own sex hormones. "Hormonal
treatments have been available for ages, but they've involved really unpleasant
things like being castrated. For that reason, doctors have been reluctant
to use it and have mostly given it only in advanced prostate cancer,"
Peto said. "And the hormonal drugs that used to be available were pretty
horrible. But now the drugs are a lot nicer than they were and they are
getting better all the time."
The more recent drugs,
such as Casodex, seem to produce the desired effect, generally without
impotence, he said. "Back in the early '80s, there was a widespread belief
that hormonal treatment just didn't work for breast cancer and prostate
cancer," Peto said. "There was a general feeling that it may somewhat
delay recurrence but that it was going to do little or nothing for survival.
It's just not true." "Hormonal treatments for these things have probably
saved more lives than any single cancer drug," Peto said. The chances
of surviving prostate cancer vary widely across regions and depend on
how early the tumor is detected.
[Back]
Prostate
Research Promising,
But Screening Remains Vital- (HealthDayNews-19/09/2003)
A drug used to combat
baldness can cut the risk of prostate cancer by 25 percent. A newly discovered
gene appears to play a key role in governing the spread of cancerous prostate
cells to other parts of the body. Frequent exercise, maintaining a proper
weight and routine prostate screenings seem to be significant steps to
prevent the disease's spread. These recent findings are just the latest
fruits of research into prostate cancer -- developments that have made
treatment more promising than ever before. Still, experts say, early detection
remains vitally important in efforts to combat the disease, which will
afflict one in six American men in his life. And that's a message men's
health experts will be promoting during September, Prostate Cancer Awareness
Month.
Among the latest
findings: · U.S. researchers reported in July that men who took the baldness
drug finasteride for seven years had a 25 percent lower chance of getting
prostate cancer, compared with those who took a placebo. The federally
sponsored study marked the first time it was shown a drug could prevent
prostate cancer.
· University of Michigan
researchers found a gene that may be key to stopping the spread of prostate
cancer. The gene, designated RKIP, which produces the RKIP protein, can
stop cancer cells from leaving the prostate and entering the bloodstream,
the researchers reported in June.
· A study of 1,117
men with localized prostate cancer found those at high risk of having
the disease spread beyond the gland were more likely to be obese and to
exercise less than twice a week. These men also were less likely to have
had annual prostate screenings. By contrast, men with the lowest risk
of cancer progression kept their body weight down, got regular exercise
and had routine prostate cancer screenings, researchers from the University
of Texas M.D. Anderson Cancer Center reported in April. "It's a remarkable
time to be taking care of people with this disease," says Dr. Ian M. Thompson,
a urologist at the University of Texas Health Science Center and the lead
researcher in the study of the baldness drug. With all the advances in
prostate research, he says, "The prognosis is a lot better than 20 years
ago."
Progress in prevention
and treatment notwithstanding, experts say screening for prostate cancer
remains crucial. "It's a very simple issue: Prostate cancer detected early
is often much more treatable than when discovered late," says Dr. Richard
Atkins, president and chief executive officer of the National Prostate
Cancer Coalition. "Late-stage prostate cancer is very difficult to control
and it, sadly, remains too often a lethal disease."
The prostate gland,
part of the male reproductive system, is about the size and shape of a
walnut and weighs about an ounce. It's located below the bladder, in front
of the rectum, and its main function is producing fluid for semen. Prostate
cancer, with 220,000 new cases diagnosed each year, is the most commonly
diagnosed cancer among men in America, representing about 30 percent of
all new cancer cases in males, the National Prostate Cancer Coalition
says. The disease kills almost 29,000 American men annually, the coalition
says. Early prostate cancer often does not cause symptoms, the National
Cancer Institute says. But the NCI says there are potential signals to
watch for. They include a need to urinate frequently, especially at night;
difficulty starting urination or holding back urine; the inability to
urinate; weak or interrupted flow of urine; painful or burning urination;
difficulty having an erection; painful ejaculation; blood in urine or
semen; or frequent pain or stiffness in the lower back, hips or upper
thighs.
Atkins says men may
feel threatened by the prospect of screenings. "The male psyche is one
where he is supposed to be strong, invincible and invulnerable," he says.
"To go to a doctor, to go see a health-care practitioner, in some ways
conveys that that Adonis body may have things that go wrong with it. And
that's very threatening to men." Screenings for prostate cancer, which
take less than 10 minutes, consist of measuring the blood levels of a
chemical called prostate-specific antigen (PSA), and a digital rectal
exam. The American Cancer Society recommends annual screenings for men
50 and older -- and screenings starting at 45 for those considered at
higher risk. These men include blacks and those who have a close family
member who was diagnosed with prostate cancer at an early age. But even
men at high risk for the disease often don't get the screenings. "Awareness
is a huge issue," Thompson says. "It astounds me that, for example, African-American
men or a man with a family history of [prostate] cancer wouldn't have
a discussion with a doctor about prostate cancer."
[Back]
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