Put in the simplest way, no one
knows what causes some men to get prostate cancer while other men don't.
Scientists and clinical researchers are working very hard to try to
discover the answer to this very basic question. We hope they will find
the answer soon. In the meantime, here are most of the things we do know.
The recognized risk factors for prostate cancer (i.e., things that make it
more likely that a particular man may get this disease) include age, race
or genetics, and environment. Approximately 184,500 American men are
expected to be diagnosed with prostate cancer in 1998. This is compared to
165,000 in 1993. In other words, the incidence of prostate cancer appears
to have been rising slowly ... but in fact it rose rapidly from 1993 to
1996 and then fell again.
Also in 1998, the number of American men who are predicted to die of
prostate cancer is predicted to be 39,200. Approximately 3% of all deaths
of American men are currently believed to be caused by prostate cancer.
This is a large number of people, but it means that only three men in 100
will actually die of the disease.
The American Cancer Society (ACS) is, in fact, for 1998, projecting a
decline in new cases of prostate cancer and in prostate cancer deaths.
This is the first time we have ever seen a projected decline in these
numbers at the time the ACS issues its annual projections.
The fact that more American men will be found to have prostate cancer in
1998 compared to 1993 is not necessarily because more men are getting
prostate cancer. It is in fact much more likely that we have become better
at finding prostate cancer. At the beginning of 1997, it was
projected that over 330,000 men would be diagnosed with prostate cancer in
that year. That figure had to be significantly revised downward as new
data became available. However, men are living
longer than they used to, so their chances of living long enough to
get prostate cancer are increased.
The importance of genetics
If your brother or your father or
your uncle has or had prostate cancer, then there is an increased chance
that you will have prostate cancer. In other words, for many men the risk
of prostate cancer is associated with a family history of the disease.
However, this does not mean that just because your father had
prostate cancer you will get prostate cancer! It does mean that the
more relatives you have who had or have prostate cancer, the greater is
your risk. This is important and affects when a man should start to have
for signs of prostate cancer.
As with other diseases, scientists and other researchers are racing each
other to find genes which are common to individuals with prostate cancer.
In a variety of cancers (breast cancer, renal cell carcinoma, and others)
genes have now been found which are specifically related to these cancers
in some families with a very high incidence of that particular disease.
Some genes have also been identified that may be significant in the
development of certain types of prostate cancer. However, these genes are
just one step on the way to greater knowledge. Their discovery and
isolation will not immediately lead to genetic tests for prostate cancer
in most individuals, let alone to some form of universal cure for this
You are likely to hear more and more about the genetics of prostate cancer
in years to come, along with references to genes like p53, Her-2,
neu, and others, most of which will have minimal actual impact on
your personal situation.
The significance of race
Prostate cancer is much more common
in some races than in others. For example, Japanese men living in Japan
have an extremely low incidence of prostate cancer. By comparison African
American men are at very high risk of this disease. Why is this? We don't
know. What we do know is that it isn't just about their genetics and
heritage, because men of Japanese origin living in America have a similar
risk of prostate cancer as any other average American man living in the
same area! However, race can be an important factor in determining when a
man should begin to have regular check-ups
for signs of prostate cancer.
The age factor
As you grow older, your chance of
having a diagnosis of prostate cancer increases. In fact, we believe that
one of the reasons that prostate cancer is now so much more common than it
was 50 years ago is very obvious: more men live longer today than they did
50 years ago. If you live longer, your chance of having a diagnosis of
prostate cancer goes up proportionally.
The average age of men diagnosed with prostate cancer in America is still
over 60 years (although diagnosis in younger men is much more common than
it used to be). And the range of ages is very wide. Cases of prostate
cancer have first been seen in men in their twenties and in men in their
What about diet and the
There is a great deal of
circumstantial evidence that appears to support the idea that diet is
important in the avoidance of prostate cancer. On the other hand, despite
a great deal of effort to prove connections between diet and prostate
cancer, we have totally failed to do this. One relatively recent major
study has clearly linked prostate cancer risk with saturated fat intake.
The most likely situation is that a good, well balanced diet which is high
in fruit and vegetables and relatively low in red meat and fats will be
better for you than a diet that is high in red meat and fats. This is true
generally, and has nothing especially to do with prostate cancer! Eating
well is good for you! There is no known diet that will prevent prostate
cancer -- and there probably never will be!
Roughly the same is true of the environment. The cleaner your environment
the less likely you are to be at risk of prostate cancer. But then that is
true for nearly all cancers, and explains why smoking is such a
particularly foolish thing to do if you want to avoid cancer. Smoking
introduces pollutants directly into your lungs, and from there to almost
every other organ of the body. You might as well go and stand beside the
nearest major freeway and inhale car and truck exhaust fumes all day! Once
again, however, there is no perfectly clean environment that will allow
you to live without the risk of prostate cancer!
Having said that, why is it that when Asian males move from Asia to
America their risk of prostate cancer rises so rapidly? Is it the change
in diet? Is it the change in the environment? Is it just that they are
more likely to get tested for prostate cancer in America than they were in
Asia? What is going on? Unfortunately, we don't know.
Is prostate cancer related to
One question that crops up over and
over again is whether having a vasectomy (the procedure that stops a man
from making a woman pregnant) can lead to a later diagnosis of prostate
First of all, it has to be said that men who have vasectomies do
appear to be more likely to have a diagnosis of prostate cancer 20 years
later than men who do not have vasectomies. However, it also has to
be said that there is absolutely no evidence whatsoever of a cause and
effect relationship. Indeed, there is good reason to believe that this is
a statistical coincidence that has to do with the attitudes to health of
men most likely to have vasectomies.
Basically, men who have vasectomies exhibit what is widely described as
"health-seeking" behavior. In other words, they are the type of
men who look after their health, tend to go for regular check-ups, and
generally have a lifestyle which could be considered as
"healthy." They are presumed to be more likely to have
vasectomies because they have considered that the risks associated with a
vasectomy are far lower than the risks associated with their wife/partner
having a late or unwanted pregnancy.
Now it is also reasonable to suppose that men who exhibit health-seeking
behavior are more likely to seek regular prostate examinations as part of
that behavior. This immediately implies that the same men who seek
vasectomies are more likely to have a prostate examination than the men
who do not have vasectomies. Therefore these men are more likely to be
diagnosed with prostate cancer!
The bottom line is that men who have vasectomies are somewhere between 1.5
and 2.0 times more likely to have a later diagnosis of prostate cancer
than men who have not had a vasectomy ... but that we have no reason to
believe that there is any connection between the two.
Are all cases of prostate cancer
equal in risk?
Bluntly, no they aren't. One of the
most infuriating problems is that for many men a diagnosis of prostate
cancer is not significant! If you look at the prostates taken from 100
American men over 50 years old who die in car crashes and similar
accidents, that is men who never showed any clinical sign of prostate
cancer while they were alive, you can, in fact, find small areas of cancer
in the prostates of about 30 of those men (30%). Those men could have
lived for years with those small areas (foci) of prostate cancer -- or
some of them could have been diagnosed with clinically significant
prostate cancer just a few months later if they had lived. If you do the
same thing with American men over 90 years old, you find that 90% of them
have microscopic evidence of prostate cancer.
These small areas of prostate cancer tissue that do not develop into
clinically important disease are often called "latent" prostate
cancer. For an average American man of 50 years of age, with a reasonable
life expectancy of another 25 years, the chance that he will develop a
microscopic focus of so-called "latent" prostate cancer tissue
is estimated to be 42% (that is, 42 of 100 such men will get such a
microscopic focus). However, the chance that the same man will get
clinically significant prostate cancer (that is, prostate cancer that is
associated with clear signs or symptoms of the disease) is only 9.5%.
Finally, of the same 100 men, only about three will actually die of
prostate cancer. So you can clearly see that while many men may get
prostate cancer, it will actually affect relatively few of them very
seriously. It is often said that most men are much more likely to die with
prostate cancer than because of this disease.
We do not yet know how to tell which men with a small focus of prostate
cancer are most likely to go on to get clinically significant disease.
This is one of the most important things to understand about prostate
cancer. It affects almost everything about the disease. It is something
you should think about and discuss
with your doctor
before you ask to have specific tests for prostate cancer and most
certainly before you receive treatment for early stages of prostate
cancer which are confined to the prostate. You may be better off not
having the specific tests if you have absolutely no reason to believe you
are at risk for prostate cancer. And even if you are diagnosed with a
small focus of cancer confined to the prostate, you may be better off if
the doctor practices so-called watchful
waiting rather than attempting
curative therapy. You and your doctor need to make decisions like this together,
and you should ask your doctor for all the information he or she can
give you before you take those decisions.
and diagnosis of prostate cancer
gives you the basics
DRE, PAP, RTPCR, TRUS, and other diagnostic acronyms
can help you with some important and common technical terms
on Earth is PIN?
may be useful if you are told you have prostatic intraepithelial neoplasia
stages of prostate cancer
can help you understand the different "stages" of this disease
will help you understand the "grade" of your disease
and Using Partin Coefficient Tables
can help you to integrate information on your PSA, your Gleason grade,
and your clinical stage in making decisions about your risks
there are no easy answers
gives you more of the scoop on just how difficult
it is to make good decisions about prostate cancer
and Using Partin Coefficient Tables
can help you to integrate information on your PSA, your Gleason grade, and
your clinical stage in making decisions about your risks
of prostate cancer: an overview
can offer you a general introduction to the treatment of all stages of
of localized prostate cancer
can give you specific and detailed information on the treatment of disease
which is confined to the prostate and the seminal vesicles
of locally advanced prostate cancer
will give you specific information on treatment of locally advanced but
non-metastatic prostate cancer
of advanced prostate cancer
can give you specific information about the treatment of metastatic
of hormone-refractory prostate cancer
will give you information about the treatment of prostate cancer
which is no longer amenable to hormone therapies
Clinics and Centers
a list of US-based prostate cancer clinics and clinical centers with web
sites which offer additional information
offers review articles on different aspects of prostate cancer and its
used to treat prostate cancer
tells you about some of the drugs that are commonly used