Prostate Cancer: FAQs
Last Revised July 11, 1995
The answers to questions listed below are based on information available from the National Cancer
Institute and other reputable resources. Please note that these answers are general in nature and are
not intended to provide specific advice to or for individual patients. Individual patients should always
discuss any specific course of action regarding the detection, diagnosis, or management of any disorder
with their personal physician(s).
Frequent questions asked by patients
What and where is the prostate?
What is prostate cancer?
What are the symptoms of prostate cancer?
Can prostate cancer be found before a man has symptoms?
Is prostate cancer testing generally a good idea?
What is a digital rectal examination?
What is a PSA test?
How likely am I to get prostate cancer?
Can prostate cancer be prevented?
What is the right way to treat prostate cancer?
Does treatment of prostate cancer have side effects?
Frequent questions asked by health professionals
Is it possible to prevent prostate cancer?
Has prostate cancer incidence actually increased?
Who is at risk for prostate cancer?
Why have we seen an increase in the incidence of prostate
cancer?
Why have we seen an increase in prostate cancer
mortality?
Have prostate cancer survival rates changed?
Do prostate cancer incidence and mortality rates differ by race in the US?
Why are prostate cancer rates particularly high among African
Americans?
What are the standard forms of treatment for prostate cancer?
What are the promising experimental treatments for prostate
cancer?
Are there new drugs in development for management of prostate
cancer?
Answers to frequent questions asked by patients
What and where is the prostate?The prostate is a part of every man's reproductive
system. In the average mature male, it is about the size of a walnut. The prostate is located
immediately below the bladder and in front of the rectum. You can find more information in the
section Where is your prostate and what does it do?.
What is prostate cancer?
Prostate cancer is the most common type of cancer in men in
America. It is usually found in older men, and the risk of having prostate cancer increases with age.
It is mainly found in men of 55 years and above. In this disease, cancer cells are first formed in the
prostate and can then spread (metastasize) to other parts of the body, particularly the bones and other
selected structures. For more information, see The causes of prostate
cancer.
What are the symptoms of prostate cancer?
A man can actually have prostate cancer
for many years before symptoms become apparent. When symptoms do occur, they may include one
or more of the following: frequent urination (especially at night), inability to urinate, trouble starting
or holding back urination, pain on ejaculation, a weak or interrupted urine flow, pain or a burning
feeling during urination, blood in the urine or semen, frequent pain or stiffness in the lower back, hips,
or upper thighs. However, these symptoms can also be caused by other conditions as well as
prostate cancer. If you have one or more of these symptoms, it would be wise to visit your doctor for
a check-up.
Can we find prostate cancer before a man has symptoms?
Certainly. In fact it is now
very common for prostate cancer to be detected long before symptoms could be expected to develop.
The problem is that prostate cancer often takes years to grow. We just do not know whether early
detection of this cancer -- before the symptoms become apparent -- can help to reduce the number of
deaths caused by the disease. In addition, the tests used to detect prostate cancer early in its
development do not tell us enough about how it will develop. The result is that many doctors
are still concerned about the problems that can be caused by the follow-up tests and procedures
required when prostate cancer is detected early! (You may want to look at the section Prostate cancer screening and early detection for additional
information.)
Is prostate cancer testing generally a good idea?
This is a very hard question to answer.
For some men with a family history of prostate cancer it almost certainly is a very good idea.
For other men with a history of some other chronic disease and a short life expectancy, it may well be
a very bad idea, because that man may gain little or nothing from treatment and may be taking
considerable risk and undergoing much hardship by having treatment. Each man should discuss the
benefits and risks of prostate cancer testing carefully with his doctor before deciding to have a PSA
test. Ask your doctor to explain to you what will need to be done if that PSA test is positive.
What is a digital rectal examination or DRE?
In a digital rectal examination or DRE
the physician -- while wearing a lubricated surgical glove -- inserts his finger into the patient's rectum,
thus allowing the physician to feel the prostate through the rectal wall. The apparent presence of hard
or lumpy areas in the prostate is a very strong indication of the presence of prostate cancer. (For more
information you may want to look at the section on DRE in PSA, DRE,
..., and other diagnostic acronyms.)
What is a PSA test?
The PSA or prostate specific antigen test is a blood test used to
measure the amount of a particular protein that can be found in a person's blood. This protein is only
made by prostate cells and in normal men the PSA level is usually low (less than 4.0 nanograms per
milliliter). Prostate cancer and certain other conditions can cause an increase in the PSA value
because of an increase in the amount of the prostate specific protein circulating in the blood. If the
PSA value is higher than 4.0 nanograms per milliliter in a normal middle-aged male, the doctor would
consider further testing to see whether prostate cancer could be the cause. (For more information you
may want to look at the section on PSA in PSA, DRE, ..., and other
diagnostic acronyms.)
How likely am I to get prostate cancer?
That is one of the sixty-four thousand dollar
questions! No one can answer it at the moment. However, some groups of people do appear to be
more likely to get prostate cancer than others. African Americans have one of the highest rates of
incidence of prostate cancer. Americans generally have one of the highest rates of prostate cancer. If
you have a family history of prostate cancer, you are more likely to get prostate cancer than someone
with no family history of the disease. The longer you live, the greater the chance that you will have
(at least) prostate cancer cells in your prostate -- although that doesn't necessarily mean that you need
treatment. You may want to look at The causes of prostate cancer for
more information.
Can prostate cancer be prevented?
No, not at the moment. There is one major clinical
trial to see whether a pharmaceutical called finasteride may be able to prevent the development of
prostate cancer. Also, it now appears clear that if you eat a very large amount of saturated fat in your
diet you are more likely to have prostate cancer than if you eat a diet lower in fat. For additional
information look at the section on Prostate cancer prevention and the
report on prostate cancer and its association with diets high in
saturated fat.
What is the right way to treat prostate cancer?
Four methods are often used in the
United States to treat prostate cancer today. The first is surgery to remove the cancer. The second is
radiation therapy, which uses different types of high energy radiation to kill the cancer cells. The third
is cryotherapy or cryoablation, which is a way of freezing the prostate to destroy the organ.
(Cryotherapy is widely considered to be an experimental procedure at this time.) The fourth is
hormonal therapy, in which different types of hormone are used on their own or in combination with
other methods to stop the cancer cells from growing. All these methods have benefits and risks.
There is no one "right" way to treat prostate cancer. The treatment that offers the best option for one
patient may be quite wrong for another patient. Making the proper choice of treatment for a particular
patient is sometimes very difficult. The doctor will want to consider the age and general health of the
patient, the extent of the patient's disease, how the patient feels about the different treatment options,
and what the risks are for each possible treatment. It is true that for some patients treatment may be
unnecessary or even unwise. In these patients the doctor will usually practice what is called "watchful
waiting," and will monitor the patient carefully by giving regular check-ups.
Does treatment of prostate cancer have side effects?
Every form of treatment currently
available for the management of prostate cancer is associated with significant risks and possible side
effects. If you are told that you have prostate cancer that needs to be treated, you should ask your
physician to explain to you carefully what those risk and side effects are. If you look at the list of contents of The Prostate Cancer InfoLink, you will find several sections
on the treatment of prostate cancer. You could look there for more information.
Frequent questions asked by health professionals
Is it possible to prevent prostate cancer?
No, not as far as we know at this time. It has
been strongly argued (with good but probably not conclusive supporting evidence) that if a man
wishes to lower his risk of developing prostate cancer he should avoid a diet high in saturated fats.
There is an ongoing clinical trial involving 18,000 men over 55 years of age to examine the possibility
that long-term finasteride (Proscar/Merck & Co.) treatment may be able to lower the risk of prostate
cancer in appropriate males. For more information about this trial, see Prostate cancer prevention.
Has prostate cancer incidence actually increased?
According to the National Cancer
Institute, the incidence of prostate cancer, which is the number of new cases of prostate cancer
diagnosed per year per 100,000 men, rose an average 3.3% per year from 1973 to 1990 (which is the
last year for which data are currently available). Between 1975 and 1979 the rate of increase was
2.2% per year. From 1986 to 1990 it was 8.6% per year. Finally, from 1989 to 1990 it was 16.0%.
Based on these figures, the answer certainly appears to be a resounding, "Yes." However, the
availability of PSA testing in the late 1980s had a profound effect on our ability to detect prostate
cancer early in the course of the disease. We simply do not know at this time whether this ability has
resulted in us finding large numbers of prostate cancer patients who in fact were present long before
we were able to diagnose early stage disease. Some physicians have also started to suggest that
current predictions of expected numbers of new prostate cancer patient diagnoses for 1995 and 1996
are likely to be considerable overestimates based on data already available from some tumor
registries.
Who is at risk for prostate cancer?
It is clear that the fundamental risk factor for
prostate cancer is age. From 1986 to 1990 the average annual incidence rate was 22.7 cases per
100,000 men under age 65 and 884.1 cases per 100,000 men of age 65 and over. Thus if you were
over 65 you were nearly 40 times more likely to have prostate cancer than if you were under 65! It is
also apparent that African Americans have significantly higher incidence than white Americans, while
Asian immigrants to the US have much lower incidence rates. One recent report appears to give
credence to a long-held belief that men with diets high in saturated fats are at greater risk of
developing prostate cancer than men with low fat diets. After the publication of a number of studies,
there now appears to be relatively little evidence to support earlier suggestions that men who have a
vasectomy are at any greater risk of developing prostate cancer than other men who do not have a
vasectomy. Again, however, this conclusion is not definitive.
Why have we seen an increase in the incidence of prostate cancer?
It is generally
believed that the single most important reason for the increase in the incidence of prostate cancer is
new tests and procedures that deliberately or incidentally allow the detection of asymptomatic prostate
cancer. The single most important one of these tests is almost certainly the PSA test, which first
became available in the 1980s and started to achieve widespread use in the late 1980s and early 1990s.
It has been reported by the American College of Surgeons that in 1984 only 5.8% of prostate cancer
patients had been given a PSA test; by comparison, in 1990, 68.4% of prostate cancer patients had
been given a PSA test. It is probable that today (July 1995) close to 100% of patients diagnosed with
prostate cancer will have been given a PSA test.
Why have we seen an increase in prostate cancer mortality?
By comparison with the
increase in the incidence of prostate cancer from 1973 to 1990 (reported at 3.3% per year), the
increase in mortality from this disease is still relatively small at an average of 1% per year over the
same time period. This is even more striking when one considers the period 1986 to 1990, when the
average increase in the incidence of the disease was 8.2% per year and the average increase in the
mortality was only 2.6%. There are serious questions associated with these data. Four major reasons
for the increase in prostate cancer have been proposed. (1) There has been a general increase in the
longevity of men, and thus more men are living to ages at which they might expect to die from
prostate cancer. (2) There has been a considerable decline in mortality from heart disease since the
late 1960s. (3) As more men are diagnosed with prostate cancer, their deaths are being attributed to
this disease even if the actual causes of death are not related to their cancer. (4) Unidentified factors
could be contributing to a genuine increase in age-specific mortality for males of age 85 and over --
which is the group of men in which prostate cancer mortality has most clearly increased.
Have prostate cancer survival rates changed?
According to the epidemiological data,
survival rates have indeed increased over time based on 5-year survival data from the time of
diagnosis. What is not yet clear is whether this apparent increase in the survival rates is a real
increase. We are clearly diagnosing prostate cancer earlier in the course of the disease. As a
consequence, we know that prostate cancer patients must be living for a longer time with the
knowledge that they have prostate cancer. Does that mean that we have increased their survival time?
No, it does not. All that means is that we have increased the time that they are living with a diagnosis
of prostate cancer. On the other hand, there have been several major advances in our ability to treat
patients with prostate cancer, and some of these have been clearly associated with increases in disease-
free survival, cancer-specific survival, and overall survival in very carefully controlled clinical trials
involving hundreds of patients. The likelihood is that the apparent increase in prostate cancer survival
rates includes two components: an increase due to earlier diagnosis and an increase due to
improvements in therapy.
Do prostate cancer incidence and mortality rates differ by race in the US?
Yes,
apparently they do. African Americans appear to have considerably higher incidence rates than white
Americans. Indeed, it appears that Africa Americans have the highest rate of incidence of prostate
cancer in the world. Furthermore, the prostate cancer mortality rate among African Americans is also
considerably higher than it is among white Americans. There is considerable discussion over the exact
degree to which these two rates differ between African and white Americans. We hope to provide the
most recently available data on this issue shortly.
Why are prostate cancer rates particularly high among African Americans?
The only
clear reason why the incidence and mortality rate for prostate cancer should be higher among African
Americans than they are among the rest of the population is hormonal. The progress of prostate
cancer is significantly impacted by levels of the male hormone testosterone, and African Americans
have a higher average level of testosterone in their blood than white Americans. The simplistic
conclusion is that the higher testosterone level is directly related to a higher rate of incidence of
prostate cancer and a higher rate of mortality. However, there are also some suggestions that
differences in diet between African Americans and white Americans may also be involved. A great
deal more study will be required before we can draw any absolute conclusions.
What are the standard forms of treatment for prostate cancer?
The treatment of
prostate cancer depends upon a variety of factors, including the age and general health status of the
patient, the stage and grade of the cancer, and the precise results of various prognostic tests now
available. Four forms of patient management are considered to be "standard practice." The first is
commonly called "watchful waiting," but might be better described as "active surveillance." In this
situation, no actual treatment is given to the patient, but the progression of his disease is carefully and
regularly monitored using PSA tests and other forms of prognostic assessment. Such active
surveillance is considered by many physicians to be particularly appropriate for prostate cancer patients
diagnosed late in life whose prostate cancer is thought to be unlikely to progress to a serious clinical
stage during the remainder of the patient's lifetime. Two forms of therapy are considered standard
options for the treatment of cancer that is entirely confined to the prostate: surgical removal of the
prostate gland (radical prostatectomy) or radiation therapy targeted to the pelvic area generally and (as
far as possible) to the prostate gland in particular. When the cancer is definitely confined to the
prostate, these two forms of therapy are both given with the intent of curing the cancer. The fourth
form of standard therapy is hormone therapy and is applied to patients in whom the cancer has
definitely escaped from the confines of the prostate. Therapy in this situation is not considered to be
curative, but is intended to slow the progression of the disease and alleviate symptoms commonly
associated with such progression. There are a variety of available options for hormone therapy,
ranging from orchiectomy (surgical removal of the testicles) to sophisticated forms of androgen
deprivation using drugs that impact levels of testosterone and other males hormones.
What are the promising experimental treatments for prostate cancer?
The most
widespread form of experimental treatment for prostate cancer in the US today is probably cryotherapy
(also known as cryosurgery and cryoablation). Many physicians and patients consider this form of
therapy to be a major advance in the management of prostate cancer that is definitely confined to the
prostate, offering benefits superior to those of radical surgery or radiotherapy. Other physicians argue
that there is no data yet available to demonstrate the benefits claimed by the proponents of this new
technique. Basically, cryotherapy involves controlled freezing of the prostate gland with liquid
nitrogen to temperatures so low that the tissue is actually killed. Thus it is proposed to have effects
comparable to radiation therapy. Until the completion of at least one well constructed clinical trial
that carefully compares the results of cryotherapy to other forms of therapy in a randomized,
controlled manner, we will not know whether cryotherapy actually offers superior or inferior results to
any other possible form of therapy.
Are there new drugs in development for management of prostate cancer?
An
increasingly large number of new drugs are currently under investigation for the treatment of prostate
cancer on their own or in combination with other drugs or as additions to other forms of standard
therapy such as radical surgery or radiation therapy for patients with selected stages of disease. The
new drugs on which the most information is currently available include Suramin, bicalutamide
(Casodex/Zeneca Pharmaceuticals), and nilutamide (Anandron/Hoechst-Roussel). Suramin is in clinical
trials for the management of patients with advanced prostate cancer who have failed standard hormonal
therapies. Bicalutamide and nilutamide are new antiandrogens which are believed to have similar
clinical effects to flutamide (Eulexin/Schering). Applications to market these two agents have been
submitted to the Food and Drug Administration (FDA) in the US. Bicalutamide and nilutamide are already available in some other
countries. It should also be observed that some other older pharmaceuticals are also
being tested for their potential value in the treatment of prostate cancer, e.g., mitoxantrone
(Novantrone/Immunex). According to the Pharmaceutical Research and Manufacturer's of America
(PhRMA), there are about 25 pharmaceuticals currently in various stages of development or clinical
trial which may have value in the treatment of prostate cancer. Patients should only receive
unapproved pharmaceuticals within clinical trials or other guidelines approved by the FDA.
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