Prostate cancer
Alternative names:
cancer of the prostate
Treatment:
Treatment options vary based on the stage of the tumor and
may be controversial. In the early stages, surgical removal
of the prostate (prostatectomy)
and radiation therapy
may be used to eradicate the tumor.
Metastatic cancer of the prostate may be treated by hormonal
manipulation (reducing the levels of testosterone
to prevent further spread of the cancer)
or chemotherapy.
MEDICATIONS:
Hormonal manipulation aims at lowering testosterone levels.
This can be done with an orchiectomy or with medications.
Since prostate tumors are dependent on testosterone, reduction
of the level of testosterone is often very effective in preventing
further growth and spread of the cancer. Hormonal manipulation
may halt the growth of advanced prostate cancer or relieve
symptoms in people with metastatic disease.
Synthetic drugs that mimic the function of LHRH (luteinizing
hormone releasing hormone) are being used to treat advanced
prostate cancer. This includes Lupron (leuperolide acetate)
and Zoladex (goserelin acetate). These medications suppress
gonad (testicular) stimulation of testosterone production.
They must be given by injection on a monthly basis. Possible
side effects include gynecomastia
(development of breasts in males), nausea,
and vomiting.
Antiandrogens are typically given in conjunction with the
LHRH-like drugs to avoid a transient increase in testosterone.
This medication must be taken 3 times a day indefinitely.
Possible side effects include gynecomastia, erectile dysfunction,
and diarrhea. These medications include: Androcur (cyproterone
acetate), Flutamide (eulexin) and Megace (megestrol acetate).
The most recent advances in hormonal treatment include once-daily
dosing of hormones with Nilandron (nilutamide) and Casodex
(bicalutamide).
A synthetic estrogen, DES (diethylstilbestrol), is often
used to reduce testosterone levels. This medication is taken
once a day. Possible side effects include gynecomastia
(development of breasts in males), nausea,
and vomiting.
When standard hormone manipulation fails, other alternatives
are needed. Other hormonal options include:
- Intermittent Androgen withdrawal (this is done when the
tumor is thought to have become dependent on hormonal blockade)
- Ketoconazole - complications: nausea, vomiting, and severe
liver toxicity
- Aminoglutethimide (Cytadren) - complications: lethargy,
weakness, fever, rash
- Hydrocortisone
However, when prostate cancer becomes truly refractory to
hormonal manipulation, chemotherapy is required.
CHEMOTHERAPY:
Chemotherapy is often used as a palliative (relieving symptoms
without curing the disease) treatment of prostate cancers
that are resistant to hormonal treatments. Patients survive
for a median of six to nine months from the time that their
cancer becomes hormone resistant. An oncology specialist will
usually recommend a single drug or a combination of drugs
aimed at destroying the cancer cells. Medications that may
be used to treat prostate cancer include:
- Estramustine (Emcyt)
- Etoposide
- Vinblastine
- Mitoxantrone/Prednisone
- Suramin
- cyclophosphamide
- methotrexate
- doxorubicin
- 5-fluorouracil
- cisplantin
- mitomycin C
- decarbazine
A patient is usually hospitalized for the first few doses
of chemotherapy to monitor for possible side effects. Response
is measured by the degree of PSA reduction. Most people receive
their chemotherapy (after the initial dose) on an outpatient
basis at a clinic or physician's office. Possible side effects
are numerous and specific to a given chemotherapy drug. Chemotherapy
can cause hair loss, low blood counts, and nausea.
SURGERY:
Surgical treatment is usually only recommended after thorough
evaluation and discussion of the treatment options. A man
considering surgery should be aware of the expected benefit
of the procedure as well as its potential risks.
Radical prostatectomy is often recommended for treatment
of localized stage A and B prostate cancers. This procedure
is lengthy, especially if a lymph node dissection (removal)
is performed at the same time. Pelvic lymph node dissection
is performed to provide prognostic information when the Stage
> T1c, Gleason score > 7, or PSA > 10 ng/ml and is usually
performed using general or spinal anesthesia. An incision
is made through the abdomen or perineal area. Because of advances
in the procedure and in anesthesia, the average length of
hospitalization has been reduced from 7-10 days to approximately
3 days. Possible complications include impotence and urinary
incontinence, although nerve-sparing procedures can reduce
the risk of these complications. Other rare complications
include blood loss requiring a transfusion. Although the risk
of impotence is significant, certain drugs such as Viagra
(sildenafil) and Caverjet (prostaglandin E1) have relieved
many men of this complication to a large extent. Other treatment
options for impotence include intercavernosal injection, vacuum
erection devices, and penile prostheses.
ORCHIECTOMY
Metastatic cancer of the prostate may be treated by hormonal
manipulation through bilateral orchiectomy (removal of the
testicles, castration).
The resulting lower levels of testosterone prevents further
spread of the cancer. Orchiectomy is performed under general
anesthesia as a same day surgical procedure with an overnight
stay. A small incision is made in the groin area to remove
the testicle. There may be some bruising
and swelling initially
after surgery, but this will gradually subside.
OTHER SURGICAL OPTIONS
Physicians are currently evaluating the long term effects
of an investigational surgical procedure called cryosurgical
ablation of the prostate. Cryosurgery
ablation is a method of destroying the tumor by freezing the
entire prostate gland. The procedure is performed using general
anesthesia. A series of cryoprobes are inserted through the
perineum to freeze the prostate gland.
A patient will stay in the hospital 2 to 3 days after the
procedure to monitor him for potential complications, including
bleeding, infection,
tissue injury, and inability to urinate. A patient should
be able to resume normal activities within one week after
surgery. Cryosurgery ablation is now considered an alternative
to radiation therapy for people with small, localized tumors
since this procedure is associated with a lower risk of bleeding,
incontinence, and impotence
compared to standard treatments.
RADIATION THERAPY:
Radiation therapy is used primarily to treat Stage B and C
prostate cancers, or for people with localized tumors who
are not candidates for surgery for health or personal reasons.
Radiation therapy to the prostate gland may be performed in
a number of ways.
External beam radiation therapy is performed in the hospital,
usually on an outpatient basis, by specially trained radiation
therapists. Radiation therapy is administered to cure the
cancer at an early stage, as additional therapy following
prostatectomy in locally advanced cancer or in metastatic
complications in symptomatic areas. Prior to treatment, a
therapist will mark the location that is to be radiated with
a special semi-permanent marking pen. The radiation is delivered
to the prostate gland and regional lymph nodes using a device
that resembles a normal x-ray
machine. The treatment itself is generally painless, however,
there are several side effects associated with radiation therapy.
Possible side effects include loss
of appetite, fatigue,
skin reactions such as redness and irritation, rectal burning
or injury, cystitis (inflamed
bladder), and hematuria
(blood in urine). External
beam radiation therapy is usually performed five days a week
for six to eight weeks.
Interstitial Radiotherapy (Brachytherapy), another method
of administering radiation therapy to the prostate, consists
of implanting radioactive iodine, gold, or iridium in the
form of small pellets or seeds directly into the prostate
tissue through a small incision. Because the amount of radiation
involved is small, a patient receiving this therapy is not
considered radioactive. The procedure used to be done through
an abdominal incision, but is now commonly performed through
the perineum area under CT or ultrasound guidance. The advantages
of these more recent approaches include less surgical adverse
events and more accurate seed placement into the area with
disease. The advantage of interstitial radiation therapy is
that the radiation is directed at the prostate with less damage
to the surrounding tissues. This decreases the chances of
suffering from impotence and other adverse effects when compared
to external beam radiation.
Observation/Surveillance:
This is a viable treatment alternative for patients who are
elderly and not expected to live 10 years in the absence of
their prostate cancer, and for those with slow growing, low-grade
cancer. Monitoring will include:
Serial prostatic-specific antigen (PSA) blood test (usually
every 6 months to 1 year)
- Serial prostatic-specific antigen
(PSA) blood test (usually
every 6 months to 1 year).
- Bone scan and/or
CT scan to evaluate
for metastasis.
- Complete blood count
(CBC) to monitor for
signs and symptoms of anemia
indicating disease progression.
- Post void residual (PVR) to monitor for urinary retention
indicating possible disease progression.
A patient is also monitored for other signs and symptoms
indicating disease progression, such as fatigue, weight
loss, increased pain, decreased bowel and bladder function,
and weakness.
Experimental Therapies:
There are several clinical trials that offer potentially
promising therapeutic interventions. These therapies include
anti-angiogenesis drugs, which claim to eliminate tumors by
minimizing their blood supply; gene therapies, which seek
to normalize the genetic blueprints of cancerous cells; immunotherapies,
which help activate the body's natural defense mechanisms
against prostate cancer; and therapies designed to stimulate
apoptosis, or programmed cell death.
LIFESTYLE CHANGES:
Surgery, radiation therapy, and hormonal manipulation all
have the potential to disrupt sexual desire and/or performance.
Discuss your concerns with your health care provider, as some
of these dysfunctions may be temporary. Additionally, there
are several options available for managing the sexual dysfunctions
related to prostate cancer treatments depending on the reason
for the dysfunction.
MONITORING:
You will be closely monitored for progression of the disease
regardless of the type of prostate cancer treatment you receive.
Monitoring will include:
Support groups:
The stress of illness
can often be helped by joining a support
group where members share common experiences and problems.
See support group - prostate
cancer.
Expectations (prognosis):
Prognosis is determined by the age of the patient at diagnosis,
the overall health of the patient, the grade of the tumor
and the stage at diagnosis. In general, the average survival
among men who are untreated is 8-10 years for those with stage
A or B disease, 3-6 years for stage C, and 2-3 years with
stage D disease.
Frequently Asked Questions (FAQ):
Q: Should I be screened for prostate cancer?
A: This is a very difficult question to answer. For
men with a strong family history of prostate cancer it is
a very good idea. For black men, it is also advisable since
they get prostate cancer at a younger age, and the cancer
is more aggressive. For men with a history of a chronic disease
and a short life expectancy, it is probably not a useful process,
because they may gain little from treatment and must reflect
on the considerable risk of complications that may result
from undergoing treatment. Ultimately, each man should discuss
the benefits and risks of prostate cancer testing carefully
with his doctor before deciding to have a PSA test.
Q: What are considered normal PSA levels and what
can cause a rise in PSA?
A: Normal PSA levels differ according to a man's age.
Patients in their 40s will have a normal PSA of 2.4 ng/ml,
whereas a patient in his 70s will have a PSA of 6.5 ng/ml.
Men over the age of 60 typically have a rise in their PSA
level of about 0.04 ng/ml/year. A PSA level that is higher
than 10-15 ng/ml, in the absence of other findings, suggests
prostate cancer. However, there are many other reasons for
an elevated PSA including: · Urinary tract infection · An
enlarged prostate · Infection or stones in your prostate ·
A biopsy of the prostate · Surgery on your prostate (such
as TURP) · Ejaculation within 48 hours of the PSA test
Calling your health care provider:
Call for an appointment with your health care provider if
symptoms occur.
Call for an appointment with your health care provider if
you are a man, over 50 years old, who has either never been
screened (by rectal exam and PSA
level determination) for prostate cancer or has not maintained
annual evaluations.
References:
Partin AW, Potter S: NCCN practice guidelines:
Prostate cancer early detection. Oncology 13 (11A): 118-132,
1999.
Cancer Management: A Multidisciplinary Approach:
Third Edition. Edited by Richard Pazdur, MD, Lawrence R. Coia,
MD, William J. Hoskins, MD, and Lawerence D. Wagman, MD. PRR;
1999.
Relative effectiveness and cost-effectiveness
of methods of androgen suppression in the treatment of advanced
prostatic cancer. Summary, Evidence Report/Technology Assessment:
Number 4, January 1999. Agency for Health Care Policy and
Research, Rockville, MD. Available at: http://www.ahcpr.gov/clinic/prossumm.htm.
Updated Date: 05/08/00
Updated by: Bradley G. Somer, MD, Division
of Hematology-Oncology, Hospital University of Pennsylvania,
Verimed Health Network
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