What Is It?
Prostate
cancer results from the uncontrolled growth of abnormal cells in the prostate
gland. This gland produces part of the fluid in semen. It is located below the
bladder and in front of the rectum, near the base of the penis.
Prostate
cancer is one of the most commonly diagnosed cancers in American men. Many
other men have the disease, but have not been diagnosed. This is because
prostate cancer has few symptoms early on.
Prostate
cancer is common, but it is not always dangerous. This is because it usually
grows very slowly. It affects older men; the average age at diagnosis is 70.
And it's usually diagnosed before it causes any symptoms. Also, these men often
have other illnesses which may be more important to treat than a cancer that
doesn't cause symptoms.
When
cells in the prostate become cancerous (malignant), they clump together,
forming small "islands" of cancer in the prostate. In many cases, it
takes years, even decades, for this localized cancer to spread beyond the
prostate. And many of these cancers may never spread.
Researchers
do not know the exact cause of prostate cancer. But they have identified
several factors that raise a man's risk of the disease. These include:
·
Age. Autopsy studies of men who died of other causes have found
that about three-quarters or more of them have some degree of prostate cancer
by age 80. These men didn't know they had prostate cancer.
·
Race. African American men
are more likely to get prostate cancer than other men—and to be diagnosed when
the cancer is at a more advanced stage. They are also more than twice as likely
to die of the disease as white men and about five times more likely to die of
it than Asian Americans.
·
Family history. If a man's father or brother has been diagnosed with prostate
cancer, his cancer risk is two to three times higher than a man who doesn't have
family members with the disease. Researchers have identified several genetic
defects that may be more common in men who develop prostate cancer. But
overall, most experts say that inherited defects cause a relatively small
number of cancers. Recent research also links a higher risk of developing
prostate cancer in families whose female members are at higher than average
risk to develop breast cancer. A common genetic abnormality may be responsible
for an increased risk to both prostate and breast cancer.
·
Lifestyle. Men who eat a lot of
red meat or high-fat dairy products seem to have a higher risk of prostate
cancer. There is little evidence that being overweight increases the risk of
prostate cancer. However, obese men are more likely to die of the disease than
men at a healthy weight.
Symptoms
In
its early stages, prostate cancer rarely causes symptoms. In fact, most men
diagnosed with prostate cancer have no symptoms. Doctors suspect prostate
cancer if a blood test shows high levels of prostate-specific antigen (PSA).
However, if the cancer spreads to the bladder or presses on the urethra, the
tube that carries urine out of the body, it can cause:
·
a weak urine stream
·
a need to urinate often
·
an intense need to urinate
·
an inability to urinate
·
pain or burning when you urinate
·
blood in your urine or semen
·
erections that are less firm
·
a drop in the amount of semen ejaculated
·
pain or stiffness in your lower back, hips, or upper thighs.
If
prostate cancer spreads to the lymph nodes, bones, or other organs, it can
cause
·
bone pain
·
weight loss
·
anemia (a lack of red blood cells)
·
shortness of breath
·
swelling in the scrotum, penis, legs, and feet
·
fatigue.
Diagnosis
Your
doctor will ask about your symptoms, your medical history, and whether prostate
cancer runs in your family. Your doctor will want to know whether you have ever
been diagnosed with an inflamed or enlarged prostate. These conditions are not
cancerous. However, the symptoms of these conditions can be the same as
symptoms of prostate cancer.
Your
doctor will examine you and do a digital rectal exam (DRE) to feel the prostate
gland. During a DRE, the doctor inserts a gloved, lubricated finger into the
rectum. The doctor can feel part of the prostate through the rectal wall.
Swelling, lumps, firm spots, or enlargement may indicate prostate cancer.
Most
cases of prostate cancer are detected by screening for the disease with a PSA
test. PSA is a protein made by the prostate that can be detected in blood.
Prostate cancer can cause higher amounts of PSA to leak out of the prostate
into the blood. Tell your doctor if you take any medications to treat an
enlarged prostate. Certain prostate medications, such as finasteride (Proscar) and dutasteride (Avodart), can affect
PSA test results.
Although
doctors use the PSA test to detect prostate cancer, it does not give a
definitive diagnosis. That's because other conditions, such as an enlarged
prostate, can raise PSA levels. In fact, most men with a mildly elevated PSA do
not have prostate cancer. Also, some men with a normal PSA actually do have cancer.
Because
an elevated PSA level may prompt you to seek treatment, which can cause urinary
and sexual side effects, many doctors and organizations don't recommend routine
PSA screening. Instead, they suggest that men age 50 and older talk with their
doctors about the risks and benefits of screening. African American men should
talk with their doctors about PSA screening beginning at age 40.
Even
though PSA screening is the most common way prostate cancers are detected, the
test very often finds cancers that do not need to be treated. In fact, some
medical organizations now recommend not having the test performed on a routine
basis.
If
your PSA level is high, or if your DRE shows a possible problem, your doctor
may order more tests, such as a prostate biopsy. In this procedure, a needle is
used to remove small pieces of tissue from the top, middle, and bottom parts of
the prostate. Your doctor also may want to take tissue samples from any areas
that felt abnormal during the DRE. A specialist called a pathologist then
checks the tissue samples for cancer under a microscope.
If
your biopsy shows prostate cancer, the pathologist will assign a Gleason grade
to the two most common cells types in your tumor. The sum of the two grades is
the Gleason score. The Gleason score describes how abnormal the cancer cells
look compared to normal prostate cells. The score provides a rough estimate of
how fast the cancer is growing. A Gleason score of
·
2 to 4 means low-grade, nonaggressive cancer
·
5 to 7 means intermediate-grade cancer
·
8 to 10 (ten is the highest score) means high-grade, aggressive
cancer.
A
doctor will also assign a "stage" to your cancer. The stage describes
the extent of the tumor and whether it has spread. Doctors use the Gleason
score and stage to plan treatment.
Expected Duration
Once
prostate cancer develops, it usually grows slowly over many years. In a small
number of men, prostate cancer grows and spreads quickly. Almost all prostate
cancer will respond to some type of treatment. In some cases, prostate cancer
might not need treatment right away, if at all. Doctors have developed criteria
to determine which cancers need treatment and which ones can be watched. If a
watched tumor worsens, it can be treated.
Prevention
Although
the evidence is mixed, men who eat a low-fat diet rich in fruits and vegetables
may reduce their risk of prostate cancer. Older studies suggested that eating
tomatoes, which contain the antioxidant lycopene, might reduce risk. Recent
studies have questioned lycopene's value.
Some
medications have been tested to see if they prevent prostate cancer. These
include finasteride and dutasteride, drugs normally prescribed for benign
prostate enlargement. One study showed that men who took finasteride reduced
their prostate cancer risk by 25 percent. But it also found that the risk of
aggressive cancer went up in some men. Later studies found that the drug
doesn't increase aggressive tumors. Given the contradictory findings, experts
don't agree about whether to offer finasteride to men with a higher risk of
prostate cancer than normal.
Treatment
Prostate
cancer can be treated several ways. You and your doctor should weigh medical
and lifestyle issues before choosing a treatment. These include
·
the extent of your cancer
·
the chance that your cancer will grow and spread rapidly
·
your age and how long you might live
·
any health conditions that would make surgery or other
treatments riskier
·
your willingness to risk side effects.
If
your cancer is confined to the prostate gland, you have several options.
Watchful waiting. With this approach, you don't have treatment unless you begin
to have symptoms. Your doctor will monitor your cancer with DREs and PSA tests
from time to time. This strategy is a good option for elderly men who are too
ill for radiation or surgery, or who are likely to die from another medical
condition relatively soon.
Active surveillance. Men whose prostate
cancer doesn't need treatment right away may opt for active surveillance. If
you choose this approach, you will be followed more closely than with watchful
waiting. Every three to six months, you will have a PSA test and a physical exam.
You may also have a biopsy every year or two. If any of these show increased
disease activity, you can start treatment.
Radiation therapy. This treatment uses radiation to destroy cancer cells. Doctors
can deliver radiation in two ways. The first method involves directing
radiation into the body from outside the body. This is called external beam
radiation therapy. Several types exist, but the goal with each is to precisely
target the prostate and spare healthy tissue.
The
second method involves putting small radioactive pellets, or seeds, into the
prostate gland. Your doctor may call this brachytherapy, seed implantation, or
interstitial radiation therapy. In most cases, the seeds are left in place
permanently.
Your
doctor may prescribe hormone therapy to boost the effectiveness of radiation
therapy. He or she may also prescribe hormone therapy to shrink the prostate
before brachytherapy.
Side
effects of radiation therapy can include
·
erectile dysfunction (the inability to have an erection)
·
diarrhea
·
rectal bleeding and pain
·
urinary incontinence (the inability to hold urine)
·
blood in the urine
·
fatigue.
Surgery. During a radical prostatectomy, the doctor will remove your
prostate gland and seminal vesicles. (Seminal vesicles are glands that release
fluid that becomes part of semen.) The doctor may also remove the nearby pelvic
lymph nodes. During surgery, the doctor will try to do as little damage to
nearby nerves as possible. This can reduce side effects such as erectile
dysfunction and incontinence.
The
doctor may use any of several techniques. For example, he or she may remove the
prostate through an incision in the abdomen. Or he or she may operate
laparoscopically, removing the prostate and other tissues through several tiny
incisions. This is often done with the aid of a robot machine to help visualize
and remove the prostate. This is called RALP (robotically assisted laparoscopic
prostatectomy). Possible complications of prostate surgery include
·
erectile dysfunction
·
urinary incontinence
·
bowel problems
·
infection.
The
chances of dying during or right after surgery are very low.
Cryoablation. This treatment, also called cryotherapy, kills cancer cells by
freezing and then thawing them. It isn't offered at many hospitals, so finding
an expert to perform the procedure in your area may be difficult. Additional
research is needed to determine the long-term effects of cryoablation.
High intensity focused ultrasound. This treatment
destroys prostate cancer with high energy sound waves that heat cells to high
temperatures. It is not currently an approved treatment for prostate cancer.
Ongoing studies should help doctors determine if this procedure is safe and
effective.
If
your prostate cancer has grown through the prostate capsule but has not spread
(metastasized) to other organs, watchful waiting or radiation therapy (with or
without hormone therapy) are usually recommended.
If
the cancer has spread to other organs, doctors usually prescribe hormone
therapy, also called androgen-deprivation therapy. Androgens are male sex
hormones, such as testosterone.
Androgens can fuel prostate cancer. Hormone therapy reduces testosterone by
preventing the testicles from producing it. Another approach is to surgically
remove the testicles. However, few men opt for this procedure.
Side
effects of hormone therapy include
·
erectile dysfunction
·
breast enlargement
·
decreased sex drive
·
hot flashes
·
weight gain
·
nausea and diarrhea
·
a drop in bone density and muscle mass
·
changes in liver function.
If
prostate cancer has already spread to other organs at the time of diagnosis,
doctors may either start hormone therapy alone or a combination of both hormone
therapy and chemotherapy.
When
To Call a Professional
Call
your doctor right away if you notice blood in your urine or semen, or if
urination is painful, uncomfortable, or abnormal in any way.
If
you are age 50 or older, ask your doctor about the pros and cons of prostate
cancer screening. Some experts believe screening with PSA tests and DREs saves
lives because cancer can be detected early. Others say that screening causes
more harm than good. That's because some men will suffer side effects from
treatment they may not have needed. Your doctor can help you decide whether
screening makes sense for you.
If
you decide to get screened, your doctor probably will do a prostate exam and
check your PSA level every one to two years, starting at age 50. If prostate
cancer runs in your family, or if you are African American, screening may start
at age 40.
Prognosis
The
prognosis usually is excellent. Nearly all men diagnosed with localized cancer
survive at least five years. More than three-quarters of all men diagnosed with
the disease live at least 15 years. In fact, many more men die of other causes
while they have prostate cancer than die as a result of the cancer.
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