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Introduction
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Prostate cancer is the most common type of cancer
in men in the United States (other than skin
cancer). Of all the men who are diagnosed with
cancer each year, more than one-fourth have prostate
cancer.
This booklet mentions some possible causes of
prostate cancer. It also describes symptoms,
diagnosis, treatment, and follow-up care. It has
information to help men with prostate cancer and
their families cope with the disease.
Research is increasing our understanding of
prostate cancer. Scientists are learning more about
the possible causes of prostate cancer and are
looking for new ways to prevent, detect, diagnose,
and treat this disease. Because of this research,
men with prostate cancer now have a lower chance of
dying from the disease.
The Cancer
Information Service and the other NCI resources
listed in the "National
Cancer Institute Information Resources"
section provide the latest, most accurate
information about prostate cancer. Publications
listed in the "National
Cancer Institute Booklets" section are
available from the Cancer Information Service. Also,
many NCI publications may be viewed or ordered on
the Internet at http://cancer.gov/publications.
Words that may be new to readers appear in italics.
Definition of these and other terms related to
prostate cancer can be found in the Dictionary.
For some words, a "sounds-like" spelling
is also given.
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The
Prostate
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The prostate is a gland in a man's reproductive
system. It makes and stores seminal
fluid, a milky fluid that nourishes sperm.
This fluid is released to form part of semen.
The prostate is about the size of a walnut. It is
located below the bladder
and in front of the rectum.
It surrounds the upper part of the urethra,
the tube that empties urine from the bladder. If the
prostate grows too large, the flow of urine can be
slowed or stopped.
To work properly, the prostate needs male hormones
(androgens).
Male hormones are responsible for male sex
characteristics. The main male hormone is testosterone,
which is made mainly by the testicles.
Some male hormones are produced in small amounts by
the adrenal
glands.
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Understanding the
Cancer Process
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Cancer
is a group of many related diseases. These diseases
begin in cells, the body's basic unit of life. Cells
have many important functions throughout the body.
Normally, cells grow and divide to form new cells
in an orderly way. They perform their functions for
a while, and then they die. This process helps keep
the body healthy.
Sometimes, however, cells do not die. Instead,
they keep dividing and creating new cells that the
body does not need. They form a mass of tissue,
called a growth or tumor.
Tumors can be benign
or malignant:
- Benign tumors are not cancer. They can
usually be removed, and in most cases, they do
not come back. Cells from benign tumors do not
spread to other parts of the body. Most
important, benign tumors of the prostate are not
a threat to life.
| Benign
prostatic hyperplasia (BPH) is
the abnormal growth of benign prostate
cells. In BPH, the prostate grows larger
and presses against the urethra and
bladder, interfering with the normal
flow of urine. More than half of the men
in the United States between the ages of
60 and 70 and as many as 90 percent
between the ages of 70 and 90 have
symptoms of BPH. For some men, the
symptoms may be severe enough to require
treatment. |
- Malignant tumors are cancer. Cells in
these tumors are abnormal. They divide without
control or order, and they do not die. They can
invade and damage nearby tissues and organs.
Also, cancer cells can break away from a
malignant tumor and enter the bloodstream and lymphatic
system. This is how cancer spreads from
the original (primary) cancer site to form new
(secondary) tumors in other organs. The spread
of cancer is called metastasis.
When prostate cancer spreads (metastasizes)
outside the prostate, cancer cells are often found
in nearby lymph
nodes. If the cancer has reached these
nodes, it means that cancer cells may have spread to
other parts of the body--other lymph nodes and other
organs, such as the bones, bladder, or rectum. When
cancer spreads from its original location to another
part of the body, the new tumor has the same kind of
abnormal cells and the same name as the primary
tumor. For example, if prostate cancer spreads to
the bones, the cancer cells in the new tumor are
prostate cancer cells. The disease is metastatic
prostate cancer; it is not bone cancer.
This booklet deals with prostate cancer. For
information about prostate changes that are not
cancer, read NCI's booklet, Understanding
Prostate Changes: A Health Guide for All Men.
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Prostate Cancer:
Who's at Risk |
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The causes of prostate cancer are not well
understood. Doctors cannot explain why one man gets
prostate cancer and another does not.
Researchers are studying factors that may
increase the risk of this disease. Studies have
found that the following risk
factors are associated with prostate cancer:
- Age. In the United States, prostate
cancer is found mainly in men over age 55. The
average age of patients at the time of diagnosis
is 70.
- Family history of prostate cancer. A
man's risk for developing prostate cancer is
higher if his father or brother has had the
disease.
- Race. This disease is much more common
in African American men than in white men. It is
less common in Asian and American Indian men.
- Diet and dietary factors. Some evidence
suggests that a diet high in animal fat may
increase the risk of prostate cancer and a diet
high in fruits and vegetables may decrease the
risk. Studies are in progress to learn whether
men can reduce their risk of prostate cancer by
taking certain dietary supplements.
Although a few studies suggested that having a vasectomy
might increase a man's risk for prostate cancer,
most studies do not support this finding. Scientists
have studied whether benign prostatic hyperplasia,
obesity, lack of exercise, smoking, radiation
exposure, or a sexually transmitted virus might
increase the risk for prostate cancer. At this time,
there is little evidence that these factors
contribute to an increased risk.
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Detecting Prostate
Cancer |
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A man who has any of the risk factors described
in the "Prostate Cancer: Who's at
Risk" section may want to ask a doctor
whether to begin screening for prostate cancer (even
though he does not have any symptoms), what tests to
have, and how often to have them. The doctor may
suggest either of the tests described below. These
tests are used to detect prostate abnormalities, but
they cannot show whether abnormalities are cancer or
another, less serious condition. The doctor will
take the results into account in deciding whether to
check the patient further for signs of cancer. The
doctor can explain more about each test.
- Digital
rectal exam--the doctor inserts a
lubricated, gloved finger into the rectum and
feels the prostate through the rectal wall to
check for hard or lumpy areas.
- Blood test for prostate-specific
antigen (PSA)--a lab measures the
levels of PSA in a blood sample. The level of
PSA may rise in men who have prostate cancer,
BPH, or infection in the prostate.
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Recognizing
Symptoms |
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Early prostate cancer often does not cause
symptoms. But prostate cancer can cause any of these
problems:
- A need to urinate frequently, especially at
night;
- Difficulty starting urination or holding back
urine;
- Inability to urinate;
- Weak or interrupted flow of urine;
- Painful or burning urination;
- Difficulty in having an erection;
- Painful ejaculation;
- Blood in urine or semen; or
- Frequent pain or stiffness in the lower back,
hips, or upper thighs.
Any of these symptoms may be caused by cancer or
by other, less serious health problems, such as BPH
or an infection. A man who has symptoms like these
should see his doctor or a urologist
(a doctor who specializes in treating diseases of
the genitourinary
system).
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Diagnosing Prostate
Cancer |
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If a man has symptoms or test results that
suggest prostate cancer, his doctor asks about his
personal and family medical history, performs a
physical exam, and may order laboratory tests. The
exams and tests may include a digital rectal exam, a
urine test to check for blood or infection, and a
blood test to measure PSA. In some cases, the doctor
also may check the level of prostatic
acid phosphatase (PAP) in the blood,
especially if the results of the PSA indicate there
might be a problem.
The doctor may order exams to learn more about
the cause of the symptoms. These may include:
- Transrectal ultrasonography--sound
waves that cannot be heard by humans
(ultrasound) are sent out by a probe inserted
into the rectum. The waves bounce off the
prostate, and a computer uses the echoes to
create a picture called a sonogram.
- Intravenous
pyelogram--a series of x-rays of the
organs of the urinary tract.
- Cystoscopy--a
procedure in which a doctor looks into the
urethra and bladder through a thin, lighted
tube.
Biopsy
If test results suggest that cancer may be
present, the man will need to have a biopsy.
During a biopsy, the doctor removes tissue samples
from the prostate, usually with a needle. A pathologist
looks at the tissue under a microscope to check for
cancer cells. If cancer is present, the pathologist
usually reports the grade
of the tumor. The grade tells how much the tumor
tissue differs from normal prostate tissue and
suggests how fast the tumor is likely to grow. One
way of grading prostate cancer, called the Gleason
system, uses scores of 2 to 10. Another system uses
G1 through G4. Tumors with higher scores or grades
are more likely to grow and spread than tumors with
lower scores.
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A man who needs a biopsy may want to ask
the doctor some of the following questions:
- How long will the procedure take? Will
I be awake? Will it hurt?
- Are there any risks? What are the
chances of infection or bleeding after
the biopsy?
- How soon will I know the results?
- If I do have cancer, who will talk to
me about treatment? When?
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If the physical exam and test results do not
suggest cancer, the doctor may recommend medicine
to reduce the symptoms caused by an enlarged
prostate. Surgery is another way to relieve these
symptoms. The surgery most often used in such cases
is called transurethral
resection of the prostate (TURP or TUR). In
TURP, an instrument is inserted through the urethra
to remove prostate tissue that is pressing against
the upper part of the urethra and restricting the
flow of urine. (Patients may want to ask whether
other procedures might be appropriate.)
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Stages of Prostate
Cancer |
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If cancer is found in the prostate, the doctor
needs to know the stage,
or extent, of the disease. Staging
is a careful attempt to find out whether the cancer
has spread and, if so, what parts of the body are
affected. The doctor may use various blood and imaging
tests to learn the stage of the disease. Treatment
decisions depend on these findings.
Prostate cancer staging is a complex process. The
doctor may describe the stage using a Roman number
(I-IV) or a capital letter (A-D). These are the main
features of each stage:
- Stage I or Stage A--The cancer cannot be felt
during a rectal exam. It may be found by
accident when surgery is done for another
reason, usually for BPH. There is no evidence
that the cancer has spread outside the prostate.
- Stage II or Stage B--The tumor involves more
tissue within the prostate, it can be felt
during a rectal exam, or it is found with a
biopsy that is done because of a high PSA level.
There is no evidence that the cancer has spread
outside the prostate.
- Stage III or Stage C--The cancer has spread
outside the prostate to nearby tissues.
- Stage IV or Stage D--The cancer has spread to
lymph nodes or to other parts of the body.
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Treatment for
Prostate Cancer |
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Getting a Second Opinion
Decisions about prostate cancer treatment involve
many factors. Before making a decision, a man may
want to get a second opinion by asking another
doctor to review the diagnosis and treatment
options. A short delay will not reduce the chance
that treatment will be successful. Some health
insurance companies require a second opinion; many
others will cover a second opinion if the patient
requests it. There are a number of ways to find a
doctor who can give a second opinion:
- The patient's doctor may be able to recommend
a specialist or team of specialists to consult.
Doctors who treat prostate cancer are urologists,
radiation
oncologists, and medical
oncologists. Patients may find it
helpful to talk to a specialist in each of these
areas. Different types of specialists may have
different thoughts about how best to manage
prostate cancer.
- The Cancer Information Service, at
1-800-4-CANCER, can tell callers about treatment
facilities, including cancer centers and other
programs supported by the National Cancer
Institute.
- People can get the names of doctors from their
local medical society, a nearby hospital, or a
medical school.
- The Official ABMS Directory of Board
Certified Medical Specialists lists doctors'
names along with their speciality and their
educational background. This resource, produced
by the American Board of Medical Specialities
(ABMS), is available in most public libraries.
The ABMS also has an online service that lists
many board-certified physicians (http://www.certifieddoctor.org/).
Preparing for Treatment
The doctor develops a treatment plan to fit each
man's needs. Treatment for prostate cancer depends
on the stage of the disease and the grade of the
tumor (which indicates how abnormal the cells look,
and how likely they are to grow or spread). Other
important factors in planning treatment are the
man's age and general health and his feelings about
the treatments and their possible side effects.
Many men with prostate cancer want to learn all
they can about their disease, their treatment
choices, and the possible side effects of treatment,
so they can take an active part in decisions about
their medical care. Prostate cancer can be managed
in a number of ways (with watchful
waiting, surgery,
radiation
therapy, and hormonal
therapy). If the doctor recommends watchful
waiting, the man's health will be monitored closely,
and he will be treated only if symptoms occur or
worsen. Patients considering surgery, radiation
therapy, or hormonal therapy may want to consult
doctors who specialize in these types of treatment.
The patient and his doctor may want to consider
both the benefits and possible side effects of each
option, especially the effects on sexual activity
and urination, and other concerns about quality of
life. Men with prostate cancer may find helpful
information in the sections "Methods
of Treatment," "Side
Effects of Treatment," and "Support
for Men with Prostate Cancer." Also, the
patient may want to talk with his doctor about
taking part in a research study to help determine
the best approach or to study new kinds of
treatment. "The Promise of
Prostate Cancer Research" section has more
information about such studies, called clinical
trials.
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These are some questions a patient may
want to ask the doctor before treatment
begins:
- What is the stage of the disease?
- What is the grade of the disease?
- What are my treatment choices? Is
watchful waiting a good choice for me?
- Are new treatments under study? Would
a clinical trial be appropriate for me?
- What are the expected benefits of each
kind of treatment?
- What are the risks and possible side
effects of each treatment? How can the
side effects be managed?
- Is treatment likely to affect my sex
life?
- Am I likely to have urinary problems?
- Am I likely to have bowel problems,
such as diarrhea or rectal bleeding?
- Will I need to change my normal
activities? If so, for how long?
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Methods of Treatment
Treatment for prostate cancer may involve
watchful waiting, surgery, radiation therapy, or
hormonal therapy. Some patients receive a
combination of therapies. In addition, doctors are
studying other methods of treatment to find out
whether they are effective against this disease.
(The "Promise of Cancer Research"
section has information about research studies.)
Watchful waiting may be suggested for some
men who have prostate cancer that is found at an
early stage and appears to be slow growing. Also,
watchful waiting may be advised for older men or men
with other serious medical problems. For these men,
the risks and possible side effects of surgery,
radiation therapy, or hormonal therapy may outweigh
the possible benefits. Men with early stage prostate
cancer are taking part in a study to determine when
or whether treatment may be necessary and effective.
(See "The Promise of Prostate
Cancer Research" section for information
about this study.)
Surgery is a common
treatment for early stage prostate cancer. The
doctor may remove all of the prostate (a type of
surgery called radical prostatectomy)
or only part of it. In some cases, the doctor can
use a new technique known as nerve-sparing surgery.
This type of surgery may save the nerves that
control erection. However, men with large tumors or
tumors that are very close to the nerves may not be
able to have this surgery.
The doctor can describe the types of surgery and
can discuss and compare their benefits and risks.
- In radical retropubic prostatectomy, the
doctor removes the entire prostate and nearby
lymph nodes through an incision
in the abdomen.
- In radical perineal prostatectomy, the doctor
removes the entire prostate through an incision
between the scrotum
and the anus.
Nearby lymph nodes are sometimes removed through
a separate incision in the abdomen.
- In transurethral resection of the prostate (TURP),
the doctor removes part of the prostate with an
instrument that is inserted through the urethra.
The cancer is cut from the prostate by
electricity passing through a small wire loop on
the end of the instrument. This method is used
mainly to remove tissue that blocks urine flow.
If the pathologist finds cancer cells in the
lymph nodes, it is likely that the disease has
spread to other parts of the body. Sometimes, the
doctor removes the lymph nodes before doing a
prostatectomy. If the prostate cancer has not spread
to the lymph nodes, the doctor then removes the
prostate. But if cancer has spread to the nodes, the
doctor usually does not remove the prostate, but may
suggest other treatment.
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These are some questions a patient may
want to ask the doctor before having
surgery:
- What kind of operation will I have?
- How will I feel after the operation?
- If I have pain, how will you help?
- How long will I be in the hospital?
- When can I get back to my normal
activities?
- Will I have any lasting side effects?
- What is my chance of a full recovery?
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Radiation therapy (also called
radiotherapy) uses high-energy x-rays to kill cancer
cells. Like surgery, radiation therapy is local
therapy; it can affect cancer cells only in
the treated area. In early stage prostate cancer,
radiation can be used instead of surgery, or it may
be used after surgery to destroy any cancer cells
that may remain in the area. In advanced stages, it
may be given to relieve pain or other problems.
Radiation may be directed at the body by a
machine (external
radiation), or it may come from tiny
radioactive seeds placed inside or near the tumor (internal
or implant
radiation, or brachytherapy).
Men who receive radioactive seeds alone usually have
small tumors. Some men with prostate cancer receive
both kinds of radiation therapy.
For external radiation therapy, patients go to
the hospital or clinic, usually 5 days a week for
several weeks. Patients may stay in the hospital for
a short time for implant radiation.
Hormonal
therapy keeps cancer cells from getting the male
hormones they need to grow. It is called systemic
therapy because it can affect cancer cells
throughout the body. Systemic therapy is used to
treat cancer that has spread. Sometimes this type of
therapy is used to try to prevent the cancer from
coming back after surgery or radiation treatment.
There are several forms of hormonal therapy:
After orchiectomy or treatment with an LH-RH
agonist, the body no longer gets testosterone from
the testicles. However, the adrenal glands still
produce small amounts of male hormones. Sometimes,
the patient is also given an antiandrogen, which
blocks the effect of any remaining male hormones.
This combination of treatments is known as total
androgen blockade. Doctors do not know for
sure whether total androgen blockade is more
effective than orchiectomy or LH-RH agonist alone.
Prostate cancer that has spread to other parts of
the body usually can be controlled with hormonal
therapy for a period of time, often several years.
Eventually, however, most prostate cancers are able
to grow with very little or no male hormones. When
this happens, hormonal therapy is no longer
effective, and the doctor may suggest other forms of
treatment that are under study.
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Side Effects of
Treatment |
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It is hard to limit the effects of treatment so
that only cancer cells are removed or destroyed.
Because healthy cells and tissues may be damaged,
treatment often causes unwanted side effects.
Doctors and nurses will explain the possible side
effects of treatment.
The side effects of cancer treatment depend
mainly on the type and extent of the treatment.
Also, each patient reacts differently. The NCI
provides helpful, informative booklets about cancer
treatments and coping with side effects, such as Understanding
Treatment Choices for Prostate Cancer: Know Your
Options and Radiation
Therapy and You. Patients also may want to
read Eating
Hints for Cancer Patients. See "National
Cancer Institute Information Resources" and
"Other
Information Resources" for additional
sources of information about side effects.
Watchful Waiting
Although men who choose watchful waiting avoid
the side effects of surgery and radiation, there can
be some negative aspects to this choice. Watchful
waiting may reduce the chance of controlling the
disease before it spreads. Also, older men should
keep in mind that it may be harder to manage surgery
and radiation therapy as they age.
Some men may decide against watchful waiting
because they feel they would be uncomfortable living
with an untreated cancer, even one that appears to
be growing slowly or not at all. A man who chooses
watchful waiting but later becomes concerned or
anxious should discuss his feelings with his doctor.
A different treatment approach is nearly always
available.
Surgery
Patients are often uncomfortable for the first
few days after surgery. Their pain usually can be
controlled with medicine, and patients should
discuss pain relief with the doctor or nurse. The
patient will wear a catheter (a tube inserted into
the urethra) to drain urine for 10 days to 3 weeks.
The nurse or doctor will show the man how to care
for the catheter.
It is also common for patients to feel extremely
tired or weak for a while. The length of time it
takes to recover from an operation varies. Surgery
to remove the prostate may cause long-term problems,
including rectal injury or urinary incontinence.
Some men may have permanent impotence.
Nerve-sparing surgery is an attempt to avoid the
problem of impotence. When the doctor can use
nerve-sparing surgery and the operation is fully
successful, impotence may be only temporary. Still,
some men who have this procedure may be permanently
impotent.
Men who have a prostatectomy no longer produce
semen, so they have dry
orgasms. Men who wish to father children may
consider sperm
banking or a sperm
retrieval procedure.
Radiation Therapy
Radiation therapy may cause patients to become
extremely tired, especially in the later weeks of
treatment. Resting is important, but doctors usually
encourage men to try to stay as active as they can.
Some men may have diarrhea or frequent and
uncomfortable urination.
When men with prostate cancer receive external
radiation therapy, it is common for the skin in the
treated area to become red, dry, and tender.
External radiation therapy can also cause hair loss
in the treated area. The loss may be temporary or
permanent, depending on the dose of radiation.
Both types of radiation therapy may cause
impotence in some men, but internal radiation
therapy is not as likely as external radiation
therapy to damage the nerves that control erection.
However, internal radiation therapy may cause
temporary incontinence. Long-term side effects from
internal radiation therapy are uncommon.
Hormonal Therapy
The side effects of hormonal therapy depend
largely on the type of treatment. Orchiectomy and
LH-RH agonists often cause side effects such as
impotence, hot flashes, and loss of sexual desire.
When first taken, an LH-RH agonist may make a
patient's symptoms worse for a short time. This
temporary problem is called "flare."
Gradually, however, the treatment causes a man's
testosterone level to fall. Without testosterone,
tumor growth slows down and the patient's condition
improves. (To prevent flare, the doctor may give the
man an antiandrogen for a while along with the LH-RH
agonist.)
Antiandrogens can cause nausea, vomiting,
diarrhea, or breast growth or tenderness. If used a
long time, ketoconazole may cause liver problems,
and aminoglutethimide can cause skin rashes. Men who
receive total androgen blockade may experience more
side effects than men who receive a single method of
hormonal therapy. Any method of hormonal therapy
that lowers androgen levels can contribute to
weakening of the bones in older men.
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Follow-up
Care |
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During and after treatment, the doctor will
continue to follow the patient. The doctor will
examine the man regularly to be sure that the
disease has not returned or progressed, and will
decide what other medical care may be needed.
Follow-up exams may include x-rays, scans, and lab
tests, such as the PSA blood test.
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Support for Men
with Prostate Cancer |
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Living with a serious disease such as cancer is
not easy. Some people find they need help coping
with the emotional as well as the practical aspects
of their disease. Patients often get together in
support groups, where they can share what they have
learned about coping with their disease and the
effects of treatment. Patients may want to talk with
a member of their health care team about finding a
support group.
People living with cancer may worry about caring
for their families, keeping their jobs, or
continuing daily activities. Concerns about
treatments and managing side effects, hospital
stays, and medical bills are also common. Doctors,
nurses, dietitians and other members of the health
care team can answer questions about treatment,
working, or other activities. Meeting with a social
worker, counselor, or member of the clergy can be
helpful to those who want to talk about their
feelings or discuss their concerns. Often, a social
worker can suggest resources for help with
rehabilitation, emotional support, financial aid,
transportation, or home care.
It is natural for a man and his partner to be
concerned about the effects of prostate cancer and
its treatment on their sexual relationship. They may
want to talk with the doctor about possible side
effects and whether these are likely to be temporary
or permanent. Whatever the outlook, it is usually
helpful for patients and their partners to talk
about their concerns and help one another find ways
to be intimate during and after treatment.
Booklets and other useful materials are available
from the Cancer Information Service and through
other sources listed in the "National
Cancer Institute Information Resources"
section.
The Cancer Information Service can also provide
information to help patients and their families
locate programs and services.
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The Promise of
Prostate Cancer Research |
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Doctors all over the country are conducting many
types of clinical
trials (research studies) in which people take
part voluntarily. These include studies of ways to
prevent, detect, diagnose, and treat prostate
cancer; studies of the psychological effects of the
disease; and studies of ways to improve comfort and
quality of life. Research already has led to
advances in these areas, and researchers continue to
search for more effective approaches.
People who take part in clinical trials have the
first chance to benefit from new approaches. They
also make important contributions to medical
science. Although clinical trials may pose some
risks, researchers take very careful steps to
protect people who take part.
A man who is interested in being part of a
clinical trial should talk with his doctor. He may
want to read Taking
Part in Clinical Trials: What Cancer Patients Need
To Know and Taking
Part in Clinical Trials: Cancer Prevention Studies.
These NCI booklets describe how research studies are
carried out and explain their possible benefits and
risks. NCI's cancerTrials™ Web site at http://www.cancer.gov/clinicaltrials
provides general information about clinical trials.
It also offers detailed information about specific
ongoing studies of prostate cancer by linking to PDQ®,
a cancer information database developed by the
NCI.
Causes
Although researchers know several risk factors
for prostate cancer, they still are not sure why one
man develops the disease and another doesn't. (Known
risk factors, which include aging, are listed in the
"Prostate Cancer: Who's at Risk?"
section.)
Some aspects of a man's lifestyle may affect his
chances of developing prostate cancer. For example,
some evidence suggests a link between diet and this
disease. These studies show that prostate cancer is
more common in populations that consume a high-fat
diet (particularly animal fat), and in populations
that have diets lacking certain nutrients. Although
it is not known whether a diet low in fat will
prevent prostate cancer, a low-fat diet may have
many other health benefits.
Some research suggests that high levels of
testosterone may increase a man's risk of prostate
cancer. The difference between racial groups in
prostate cancer risk could be related to high
testosterone levels, but it also could result from
diet or other lifestyle factors.
Researchers also are looking for changes in genes
that may increase the risk for developing prostate
cancer. They are studying the genes of men who were
diagnosed with prostate cancer at a relatively young
age (less than 55 years old) and the genes of
families who have several members with the disease.
Much more work is needed, however, before scientists
can say exactly how changes in these genes are
related to prostate cancer. Men with a family
history of prostate cancer who are concerned about
an inherited risk for this disease should talk with
their doctor. The doctor may suggest seeing a health
professional trained in genetics.
Prevention
Several studies are under way to explore how
prostate cancer might be prevented. These include
the use of dietary supplements, such as vitamin E
and selenium. In addition, recent studies suggest
that a diet that regularly includes tomato-based
foods may help protect men from prostate cancer.
The drug finasteride
is being studied in the Prostate Cancer Prevention
Trial, which involves thousands of men across the
country who are participating for 7 years, until
2004.
Scientists are also looking at ways to prevent recurrence
among men who have been treated for prostate cancer.
These approaches involve the use of drugs such as
finasteride, flutamide, and LH-RH agonists. Studies
have shown that hormonal therapy after radiation
therapy or after radical prostatectomy can benefit
certain men whose cancer has spread to nearby
tissues.
Researchers also are investigating whether diets
that are low in fat and high in soy, fruits,
vegetables, and other food products might prevent a
recurrence. The Cancer Information Service can
provide information about these studies.
Screening/Early Detection
Researchers are studying ways to screen men for
prostate cancer (check for the disease in men who
have no symptoms). At this time, it is not known
whether screening for prostate cancer actually saves
lives, even if the disease is found at an earlier
stage. The NCI-supported Prostate, Lung, Colorectal,
and Ovarian Cancer Screening Trial is designed to
show whether certain detection tests can reduce the
number of deaths from these cancers. This trial is
looking at the usefulness of prostate cancer
screening by performing a digital rectal exam and
checking the PSA level in the blood in men ages 55
to 74. The results of this trial may change the way
men are screened for prostate cancer. The Cancer
Information Service can provide information about
this trial.
Treatment
Through research, doctors try to find new, more
effective ways to treat prostate cancer. Many
studies of new approaches for men with prostate
cancer are under way. When laboratory research shows
that a new treatment method has promise, cancer
patients receive the new approach in treatment
clinical trials. These studies are designed to
answer important questions and to find out whether
the new approach is safe and effective. Often,
clinical trials compare a new treatment with a
standard approach.
Cryosurgery
is under study as an alternative to surgery and
radiation therapy. The doctor tries to avoid
damaging healthy tissue by placing an instrument
known as a cryoprobe in direct contact with the
tumor to freeze it. The extreme cold destroys the
cancer cells.
Doctors are studying new ways of using radiation
therapy and hormonal therapy. They also are testing
the effectiveness of chemotherapy
and biological
therapy for men whose cancer does not
respond or stops responding to hormonal therapy. In
addition, scientists are exploring new treatment
schedules and new ways of combining various types of
treatment. For example, they are studying the
usefulness of hormonal therapy before primary
therapy (surgery or radiation) to shrink the tumor.
For men with early stage prostate cancer,
researchers also are comparing treatment with
watchful waiting. The results of this work will help
doctors know whether to treat early stage prostate
cancer immediately or only later on, if symptoms
occur or worsen.
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Extracted from National Cancer Institute
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