The Treatment of Prostate Cancer: An Overview
Last Revised October 10, 1997
(some procedures may have changed since)
Introduction | The problem of misstaging | Watchful waiting |
Surgery
| Cryotherapy | Radiation |
Hormone therapy | Chemotherapy
Introduction
Currently available treatment options for some stages of prostate cancer are potentially curative.
However, patients with locally advanced disease are less likely to be cured by today's treatments, and
for those patients first diagnosed with metastatic prostate cancer medicine is unable to offer hope of a
cure at the moment. This section is designed to give you a very basic introduction to the possible
treatments for prostate cancer and why they all have problems. Further, more extensive information is
available elsewhere in these Web pages.
The problem of misstaging
If your doctor finds that you have prostate cancer after carrying out a biopsy, the next question that he
has to try to answer is, "What is the stage of this cancer?" Unfortunately, this is a very hard question
to answer in any particular case except that of clearly metastatic disease.
Let us say that Hank J. recently had a DRE and a PSA, and went on to have a biopsy. Hank's
urologist found the following:
- He thought he could feel a small suspicious nodule on the left lobe of Hank's prostate when he did
the DRE.
- Hank's PSA was 8.9 ng/ml.
- The ultrasound-guided biopsy confirmed prostate cancer in one small nodule in the left lobe of
Hank's prostate, close to the capsule (or wall) of the prostate.
On a classical basis, Hank has all the indications of stage T2a disease -- locally confined prostate
cancer in one lobe of the prostate detectable by DRE.
Unfortunately, it is later discovered that Hank's prostate cancer is in fact locally advanced. Despite the
fact that there was no good reason to expect this, prostate cancer cells also are found in Hank's
seminal vesicles. Even later, despite an excellent response to surgical treatment, Hank's PSA starts to
rise again. Hank has recurrent prostate cancer.
Of course, Hank's doctor knew that this outcome was possible, and he told Hank that this was a
possibility when they discussed treatment options together. That doesn't make anyone any happier.
But it happens often.
There is a strong desire on the part of patients and physicians to want
to believe and thus to act as
though individual cases of prostate cancer are curable -- particularly
those cases of prostate cancer
which look as though they have a good chance of being curable -- like
Hank's! After all, who wants to
throw in the towel on the grounds that the worst case is bound to happen?
As a result, there is a
tendency to get the initial (clinical) stage of prostate cancer wrong.
Most often, when the stage is
wrong, the cancer is subsequently found to be of higher stage than the
doctor first thought. In Hank's
case, the cancer was actually stage T3c/No/M1a, with a tiny degree of
extension of the cancer into one
of Hank's seminal vesicles and micrometastasis to a non-regional lymph
node, but no one knew.
There is, in fact, no way that anyone could have known Hank's
precise stage at the time of
diagnosis. Even if his doctor had given him an
RTPCR test or a ProstaScint test, the degree of
accuracy of these tests is currently not sufficient to confirm distant
metastasis in one of the non-regional
lymph nodes, and given the position of the apparently small tumor clearly
confined in the prostate,
there was also no apparent need to biopsy the seminal vesicles.
The point of this discussion is only, once again, to advise you that there
are no certainties in the
treatment of prostate cancer. Despite everyone's best attempts, there will
be many occasions on which
the best is not good enough. Until we are able to develop absolutely
definitive tests that can tell any
patient whether there is any cancer outside his prostate, this situation
will continue to be the case.
Watchful waiting
It is important that you understand that "watchful waiting" or "active
surveillance" really is a form of
treatment. For carefully selected men it may well be the best possible
option. It comes with no
side effects. It avoids all of the socially problematic and expensive
aspects of treatment. Finally, if it
turns out that the cancer is not particularly active, the result can often
be that the patient easily
outlives the risk of clinically active prostate cancer.
In watchful waiting, the doctor will carefully and regularly monitor the
potential indicators of
progression, including carrying out regular PSA tests and DREs, as well as
other possible tests such as
transrectal ultrasound. Although there is a risk that the cancer will
progress, and that it may become
clinically active disease which might have been cured if the cancer had
been removed when it was
first found, on the other hand the quality of the patient's life has been
utterly unaffected by this form
of treatment.
Watchful waiting is generally practiced on patients who, for some reason,
the physician believes will
be better served by avoiding curative treatments such as surgery or
radiation. This may be because of
their age, or because of concomitant healthy problems, or just because the
patient believes strongly
that he would prefer the risk of disease progression to the risks associated
with curative treatments.
Surgery
Surgical treatment for prostate cancer is most common among younger,
healthy patients whose tumors
are believed to be confined to the prostate (i.e., stages T1 or T2). A
number of clinical tests may be
performed in an attempt to clearly rule out gross evidence that the tumor
has metastasized. These tests
potentially include a bone scan and an acid phosphatase test. Greater
detail on the use of
surgical procedures in the treatment
of localized disease
is available elsewhere in The Prostate Cancer InfoLink.
In selected patients, it has become customary to carry out a "laparoscopic
lymphadenectomy" prior to
radical surgery. A laparoscopic lymphadenectomy is a relatively new, less
invasive surgical technique
which can be used to decide whether a patient has signs of cancer in his
pelvic lymph nodes before
making the decision to go ahead with radical surgery. By knowing whether
a patient has signs of
prostate cancer in the lymph nodes, it becomes possible to make more
informed decisions about the
possible risk-benefit equation in proceeding with actual removal of the
prostate.
There are two basic forms of radical surgery for removal of the prostate:
radical retropubic
prostatectomy and radical perineal prostatectomy. The only difference
between these two techniques
which is of importance to the patient is that the surgeon uses different
routes to reach the prostate. In
radical retropubic prostatectomy the surgeon cuts down to the prostate
through the lower abdomen. In
a radical perineal prostatectomy, the surgeon cuts up to the prostate
between the anus and the
scrotum.
All forms of surgery for removal of the prostate are associated with
complications. These
include lack of bladder control (urinary incontinence), urethral
stricture (difficulty in urination),
impotence, and the normal risks associated with anesthesia and a major
surgical procedure.
There is general agreement that lower complication rates are usually found
among those surgeons who
carry out a significant number of prostatectomies on a regular basis. In
other words, practice makes
the surgeon more competent. However, even the best surgeons have patients
with unexpected
complications. Any form of prostatectomy is a major operation and has
risks attached.
Cryotherapy
Cryotherapy (also known as cryosurgery or cryoablation) is an old technique
which has been reborn as
a result of advances in technical capability. Rather than removing the
prostate (as in conventional
surgery) or using radiation therapy with different forms of x-rays,
cryotherapy is a method of freezing
the prostate and other appropriate nearby tissues to extremely low
temperatures with liquid nitrogen.
This technique is designed to kill all the prostate cancer tissue without
having to take the
risks involved in carrying out invasive surgery.
While cryotherapy is certainly an interesting and potentially important
addition to the options which
physicians can offer patients with prostate cancer, it should probably
still be considered an
investigational technique at this time. Even physicians who have carried
out several hundred
cryosurgical procedures for prostate cancer will still say that they are
unsure of the precise future role
for this form of therapy. You can find an
interesting assessment of the current
state of cryosurgery
by a well-known cryosurgeon elsewhere on The Prostate Cancer InfoLink. [The cited document was written in 1995. Cryotherapy procedures have evolved since then. - Webmaster, Phoenix5]
If you decide that cryotherapy is an option which you wish to consider,
you should certainly seek out
a physician who has considerable experience with this technique.
You should ask that
physician very specific questions about whether cryosurgery is appropriate
for you. Specifically, you
should ask whether that physician believes that cryosurgery can be used
to cure your cancer or
whether it would be given to primarily reduce the amount of cancer in your
body.
It would be most appropriate if you could find a physician who was
interested in talking to you about
cryotherapy within a carefully controlled trial comparing the effectiveness
and safety of this technique
to the effectiveness and safety of other, traditional first-line curative
treatments (i.e., surgery and
radiation therapy).
The known side effects of cryotherapy can include impotence (in about 80%
of patients), scarring of
the urethra and urinary dysfunction (which are relatively unusual), and
irritation of the bladder, the
urethra, the rectal wall, and the genitalia. This last group of side
effects can include pain on urination,
a burning sensation during urination, frequent and unexpected urination,
blood in the urine
(hematuria), and swelling of the penis or the scrotum.
Radiation therapy
[Reminder: This document was written in 1997. There have been further developments in radiation.]
Patients who elect to have some form of radiation therapy which is
intended to cure their
prostate cancer should have cancer that is confined to the prostate and/or
the surrounding tissues (i.e.,
clinical stages T1, T2, and T3). Additional information on the use of
radiotherapy in the treatment of
localized disease is available.
As with patients who elect surgery, gross metastatic disease should be
clearly ruled out prior to therapy. A lymph node dissection to establish
the status of the pelvic lymph
glands is not necessary -- however, it may be valuable in some patients.
So-called "definitive" radiation therapy is delivered using an external
beam of x-rays carefully directed
to the areas of the pelvis that include the prostate. Other forms of
radiation therapy are "interstitial
brachytherapy" (commonly known as seed implantation), in which the
radiation oncologist and a surgeon implant radioactive pellets or "seeds"
into the prostate, and those pellets radiate the prostate and the
surrounding tissue over time. It is not uncommon for brachytherapy and
external beam radiation therapy to be used in combination in
appropriate patients. (One group of radiation oncologists has given the
name "ProstRcision" to this technique.)
Like surgery, all forms of radiation therapy are associated with
complications, including acute cystitis,
proctitis, and enteritis. In addition, most series of radiotherapy
patients have been associated with some subsequent urinary and sexual
dysfunction.
As with surgery, patients are advised that better outcomes tend to be
associated with radiotherapy centers
carrying out treatment on large numbers of patients with prostate cancer.
Hormone therapy
[Reminder: this document was last revised in 1997. Hormone therapy has developed considerably since then.]
Hormone therapy is primarily used to treat patients who have prostate
cancer which is not confined to
the prostate. It is not curative. The intent of hormone therapy
is first to delay the progression
of the cancer and second to increase the patient's survival while
simultaneously maximizing his quality
of life. Greater detail on the treatment of advanced prostate cancer
with hormonal therapies is available. [The National Cancer Institute site at http://cancernet.nci.nih.gov has considerable information.]
An increasing number of options are becoming available as methods of
implementing hormone
therapy. However, they all fall into one of the following groups of
actions:
Patients who fail first line hormonal therapy may also be appropriate for
second line
hormonal manipulation prior to chemotherapy. The available options are
addressed
in the section on secondary hormonal
therapy for the
treatment of hormone-refractory disease.
The critical factors in choosing a particular form of hormone therapy can
include the cost of the
treatment (and who is paying for it), the effectiveness and safety of the
various treatment options, and
the effects of the different forms of treatment on the patient's quality
of life. It is common for
different forms of hormone therapy to be combined with each other. In
addition, it is increasingly
common to find hormonal therapies being combined with definitive therapies
as ways to provide
additional clinical coverage for the patient in case the definitive
treatment is not successful.
Chemotherapy
In the past, it was generally believed that chemotherapy had no significant
value in the treatment of
prostate cancer. In other words, people generally thought that once a
patient started to fail hormonal
therapy his options became extremely limited. Recently, however, medical
oncologists with specific
expertise in prostate cancer, such as Howard Scher, MD, at Memorial
Sloan-Kettering Cancer Center
in New York, have started to express a more positive view about some forms
of chemotherapy for
some patients.
The views expressed by Dr Scher can be encapsulated briefly as follows.
In the past, when most
patients were only diagnosed with prostate cancer when the disease was
comparatively advanced, the
patients were so sick by the time they had failed hormonal therapy that
no form of chemotherapy had
a reasonable chance of providing the patient with any benefit -- to a
great extent because the patients
were incapable of handling the toxic effects of chemotherapies. Today,
with prostate cancer being
diagnosed earlier, the patients become eligible for chemotherapy before
they have reached the degree
of sickness that we used to see. As a consequence, some forms of
chemotherapy have started to show
potential in some patients who fail hormonal therapy.
Some of the currently available information on the use of
chemotherapy and chemohormonal combinations has
been provided as one subsection
in the section on
the treatment of hormone-refractory prostate
cancer.
The Prostate Cancer InfoLink expects substantial new information on this
topic to come available in the
not too distant future.
While there is little evidence as yet that any particular forms of
chemotherapy have major clinical
impact on disease progression or survival of prostate cancer patients, the
argument put forward by Dr
Scher seems reasonable. The Prostate Cancer InfoLink would advise all
patients who are interested in
potential chemotherapy following the failure of hormonal therapy to
consider their options with great
care. Clearly the advice of one or more medical oncologists may be
appropriate. In addition, it may
well be that certain types of chemotherapy should be considered only in
a clinical trial setting. In
general it would be wise to seek treatment from a medical oncologist with
considerable specific
experience in the management of patients with hormone-refractory prostate
cancer.
Suramin is a compound that has frequently been
mentioned as having potential in the treatment of
hormone-refractory prostate cancer. While this is the case, and clinical
trials of Suramin are
proceeding, patients should understand that Suramin is a potentially highly
toxic drug, and that the
results from some trials appear not to be as positive as was once hoped.
The Prostate Cancer InfoLink
suggests that patients should only be treated with Suramin in a clinical
trial setting under the guidance
of experienced clinical investigators.
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