Health Topics:
Prostate Cancer
The treatment of prostate cancer continues to remain controversial.
This is because there are no well-controlled clinical studies regarding
any specific form of therapy. There is, however, a significant amount
of clinical experience, which has been gathered over many years
of treating patients with prostate cancer and some truths have emerged
that appear to be generally agreed upon.
In discussing the appropriateness of treatments for patients with
prostate cancer, it is very important to develop an understanding
of the probable stage and grade of the cancer. This implies that
tests will be required, including the PSA blood test, and in some
cases, an acid phosphatase, bone scan, chest x-ray, CT scan of the
abdomen and pelvis, cystoscopic exam, kidney x-rays and/or lymph
node sampling. There is a wide variety of tests, all of which are
not necessary in every patient. The sequencing of these tests is
being modified by research currently underway. These tests will
help your physician and you understand (to the best of our ability
at this date) the possibility that in your case the disease is organ-confined
and, therefore, amenable to therapies directed specifically at the
prostate gland.
In general, options for treatment of prostate cancer range from
conservative to aggressive. As mentioned previously, the discussions
regarding your particular case will be made on an individual basis
depending on several factors, including the apparent aggressiveness
of the tumor, your age, your associated medical problems, and the
probability that the tumor is confined to the prostatic area.
It is true that many men who have prostate cancer do not need to
have any therapy. This is particularly true in men who are greater
than 75 years of age, are in poor health with associated medical
problems, and who have well differentiated prostatic cancers (meaning
that their cancer under the microscope looks to be non-aggressive).
No exact age limit can be set specifically because these various
factors have to be individualized for each patient.
Watchful Waiting (Observation)
Recent studies have suggested that men who are older (72 years
of age or greater) and who develop a well-differentiated (non-aggressive)
cancer may do quite well with observation only. Observation implies
serial physical examinations and PSA blood tests to determine the
potential growth of the tumor locally or at distant sites. Research
to date suggests that approximately 10% of men fitting those criteria
(72 years old, well-differentiated cancers, early stage) who are
not treated will die of their prostate cancer within the next ten
years. Given the patient's age group, the patient can expect (during
the same time) approximately 40-50% mortality from other non-prostate
related causes. It is important, however, to remember that although
only 10% of these selected patients may die during this interval,
50-65% of them may, in fact, show progression of the disease locally,
which can cause symptoms of prostatic outlet obstruction or other
local symptoms and that as many as one-third of these patients will
develop metastasis of the disease to their bone (or elsewhere) producing
pain and requiring hormonal therapy. Nonetheless, in this select
group of patients, observation is a viable alternative to the other
more aggressive management techniques.
Aggressive therapies are aimed at the potential of curing the prostate
cancer by removing all of the cancer cells from the patient's body.
These aggressive therapies include radical prostatectomy, radiation
therapy (including external beam and brachytherapy techniques),
and cryosurgery. Each of these therapies have some specific areas
of potential benefit and also some specific associated risks. It
is important to understand these potential risks and benefits in
order to make an adequate conclusion about your treatment plan.
Radical Prostatectomy
Radical prostatectomy is a surgical procedure which can be performed
in two ways:
-
through a lower abdominal incision which allows for the simultaneous
removal of the lymph nodes which drain from the prostate gland
-
through the tissue called the perineum which lies between the
scrotum and the rectum.
The perineal approach does not, by itself, allow for removal of
the lymph nodes, which drain from the prostate and would require
a second procedure to sample these lymph nodes. This second procedure
can be done laparoscopically, i.e., through a series of scopes being
inserted into the abdominal cavity in order to visualize and remove
the lymph nodes.
Radical prostatectomy is a surgical procedure, which has been performed
for many years. It involves complete removal of the prostate, the
attached seminal vesicles (which are storage organs for the sperm)
and the distal vas (which are conduits for the seminal fluid). If
the prostatic cancer is completely contained within the prostate
gland, radical prostatectomy should offer an extremely high efficiency
in eliminating (and potentially curing) the prostate cancer. On
the other hand, even with the current practice of PSA blood testing
and improved efficiency of earlier diagnosis of prostate cancer,
as many as 20-30% of patients who are presumed to have prostate
cancer localized to the prostate gland will have signs of pathologic
evaluation of microscopic spread beyond the prostate. Thus, the
potential cure from radical prostatectomy alone probably, today
in the PSA era, ranges from 70-80%.
Technically, this surgery typically requires 2-3 hours to complete.
The patient is in the hospital for 2-3 days with the abdominal procedure
versus 1-2 days with the perineal procedure. The complications of
radical prostatectomy are impotence, which occurs in 30-50% of men
with good preoperative erections if a nerve-sparing approach to
the prostatectomy is undertaken (it is important to remember that
postoperative potency can be achieved by various different modalities
even if it is lost due to surgery or other aggressive treatments
of the prostate cancer). The other primary complication associated
with surgery is difficulty in controlling urine. Approximately 1-2%
of men will have extreme difficulty controlling urine which requires
them to wear pads throughout the day, and which usually is severe
enough that they consider some alternative way of managing their
urinary leakage, including placement of artificial sphincter or
injection of periurethral collagen.
Additionally, approximately 20-25% of men will complain of mild
stress urinary incontinence. This stress urinary incontinence, commonly
occurring in women, is an inadvertent loss of drops of urine with
coughing, sneezing, lifting, etc. This mild incontinence may require
the patient to wear a liner inside of their underclothes to control
this problem. Additional complications which may occur include bleeding
at the time of surgery and urethral stricture formation, which occurs
in approximately 2-3% of patients. By donating one's own blood (autologous
donation) and due to refinements in surgical technique, the risk
of needing to receive blood from an unknown person is less than
1%.
The advantage of surgery is that the cancer is eliminated from
the body if the patient's cancer cells are completely contained
within the prostate gland. Such patients should have nearly the
same life expectancy as men of the same age and health who never
had prostate cancer. On the other hand, as mentioned previously,
undiagnosable microscopic extension of the cancer beyond the prostate
gland may be found in 20-30% of cases. In these cases, the addition
of radiation therapy (in smaller doses) may help eliminate any residual
cancer cells. In general, radical prostatectomy is indicated for
healthy patients with a cancer that is limited to the prostate in
which the patient has at least an 8-10 year life expectancy.
Radiation Therapy
Radiation therapy uses high-energy rays to damage and destroy cancer
cells. Radiation therapy can be delivered in different ways, including
an external beam source or interstitial radiation therapy (where
needles are passed into the prostate directly and radioactive seeds
are placed into the prostate through these needles). External beam
radiation therapy generally requires approximately 35 visits to
the radiation therapist, typically each day during the work week
of Monday-Friday for seven weeks. Most studies have suggested that
interstitial radiation therapy (seeds) provide similar results in
terms of control of cancer, as there seem to be with external beam
radiation. If patients with presumably localized prostate cancer
are treated with external beam radiation therapy and rebiopsy is
performed at approximately 2 years, approximately 20-30% of patients
will still be found to have microscopic cancer within the prostate.
Prostatic brachytherapy (or interstitial implantation of radioactive
seeds) is another way of achieving high doses of radiation in the
prostate. In this procedure, needles are passed through the perineum
(the tissue between the scrotum and rectum) into the prostate under
ultrasound guidance. Tiny seeds or pellets are then deposited in
the prostate through needles. The seeds stay in permanently and
slowly produce radiation to the prostate over several months.
The best results reported with radiation therapy seem to suggest
relatively equal cure rates with surgery to approximately 6 to 7
years after treatment with most evidence suggesting that for periods
of 10, 12, or 15 years after therapy the chance of being free of
prostate cancer is less with radiation therapy than it is with radical
prostatectomy. Therefore, for the first 6-8 years after treatment
there is probably little difference in the chance of being alive
in patients who are treated with radical prostatectomy as compared
with radiation therapy. However, as the length of time increases
10 or 15 years, there is a probable advantage to radical prostatectomy
in terms of prostate cancer control.
Complications seen with radiation therapy are similar to those
with surgery including impotence in 40-60% of patients, incontinence
in 5% of patients (this typically is an urgency-type incontinence)
and stricture disease occurring in 2% of patients. A main complication,
which occurs only with radiation therapy, is related to injury and
irritation of the bladder or rectum, which occurs in approximately
5-10% of patients, some of whom have these symptoms of diarrhea
or marked irritation of their bladder causing frequent urination
through the remainder of their lifetime. The advantage of radiation
therapy is that it is generally easier for patients to tolerate
than is an operative procedure.
Radiation therapy may also be required in those patients (previously
mentioned) who are found to have microscopic extension of disease
at the time of radical surgery. In those treated with radiation,
a reduced dosage may be given which is, therefore, better tolerated
but may serve to sterilize any additional smaller number of cancer
cells which are found to be beyond the scope of the prostate at
the time of the initial surgery.
Cryoablation
Cryoablation of the prostate, or cryotherapy, is the destruction
of the prostate by the application of freezing cold temperatures.
Essentially the prostate dies of "frostbite". Metal probes
(usually 5) are positioned under ultrasound guidance through the
perineum into the area of the prostate. These probes are then cooled
by a special machine, which uses liquid nitrogen to freeze of the
prostate. Tissue temperatures within the ice ball range from -15
to -190°C. Although the mechanisms of cellular death are very
complex, simply stated, chemical reactions occur within the cell
which cause it to fail to be able to operate at such low temperatures,
and, therefore cause the cell to eventually rupture (much like liquid
in a glass bottle will rupture when exposed to an extremely cold
environment). In addition, the cells are exposed to a lack of oxygen
and also die when blood flowing to the cell freezes.
One of the unknown factors regarding cryosurgery is the long-term
effectiveness. The question of whether long-term (10-15 year cure
rates) will be equivalent to those with open surgery or radiation
therapy will not be answered for many years, given the recent nature
of the development of this technology. However, initial results
seem promising. Complications using cryosurgery include urethral
damage and tissue sloughing (dead tissue coming out of the urethra),
urinary retention (inability to urinate), irritative voiding symptoms
(feeling of discomfort or urinary infection), pelvic infection or
abscess, and rectal fistula (an abnormal connection from the prostate
to the rectum). Impotence has developed in approximately 50-70%
of patients, depending on age, but with improved experience cases
of incontinence, stricture, and rectal fistula have become rare,
occurring in approximately 1-2% of patients. Some patients require
tissue to be removed from their prostate to resume voiding.
Emotional Toll of Prostate Cancer
When a patient becomes aware that he or she has a cancer, the reaction
patients typically have is similar to that of the loss of a loved
one. The person has to come to understand the nature of the cancer
and go through various phases of adjustment, including guilt, blame,
denial and finally acceptance. Prostate cancer is generally a slower
growing tumor than many human cancers and, therefore, there is a
great deal of hope for most patients with this disease. It is important
for the patient to have a positive mental attitude toward his cancer
and to be prepared to do everything humanly possible to improve
his general state of well being and to attack the cancer with the
appropriate therapy when necessary. We hope this brief monograph
on the current approaches to the treatment of prostate cancer is
informative for you and for your family members. Please know that
our urologic oncology team is always available to discuss any problems
with you, and to answer any questions that you have regarding your
disease.
Disclaimer
The information on the Loyola University
Health System (LUHS) Web site is for educational purposes
only. It is presented in summary form in order to impart general
information relating to certain diseases, ailments, physical
conditions and their treatments. The information provided
through the LUHS Web site should not be used for diagnosing
or treating a health problem or a disease, nor is it a substitute
for professional care. Should you have any health-care related
questions or suspect you have a health problem, you should
consult your health care provider. See also Copyright
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