Enlarged Prostate
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The prostate is a walnut-sized gland that forms part of the male
reproductive system. The gland is made of two lobes, or regions, enclosed
by an outer layer of tissue. As the diagrams show, the prostate is located
in front of the rectum and just below the bladder, where urine is stored.
The prostate also surrounds the urethra, the canal through which urine
passes out of the body.
Scientists do not know all the prostate's functions. One of its main
roles, though, is to squeeze fluid into the urethra as sperm move through
during sexual climax. This fluid, which helps make up semen, energizes
the sperm and makes the vaginal canal less acidic. |
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It is common for the prostate gland to become enlarged as a man
ages. Doctors call the condition benign prostatic hyperplasia (BPH),
or benign prostatic hypertrophy.
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Normal urine flow.
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Urine flow with
BPH. |
As a man matures, the prostate goes through two main periods of
growth. The first occurs early in puberty, when the prostate doubles
in size. At around age 25, the gland begins to grow again. This
second growth phase often results, years later, in BPH.
Though the prostate continues to grow during most of a man's
life, the enlargement doesn't usually cause problems until late in
life. BPH rarely causes symptoms before age 40, but more than half
of men in their sixties and as many as 90 percent in their seventies
and eighties have some symptoms of BPH.
As the prostate enlarges, the layer of tissue surrounding it
stops it from expanding, causing the gland to press against the
urethra like a clamp on a garden hose. The bladder wall becomes
thicker and irritable. The bladder begins to contract even when it
contains small amounts of urine, causing more frequent urination.
Eventually, the bladder weakens and loses the ability to empty
itself. Urine remains in the bladder. The narrowing of the urethra
and partial emptying of the bladder cause many of the problems
associated with BPH.
Many people feel uncomfortable talking about the prostate, since
the gland plays a role in both sex and urination. Still, prostate
enlargement is as common a part of aging as gray hair. As life
expectancy rises, so does the occurrence of BPH. In the United
States in 2000, there were 4.5 million visits to a physician for
BPH.
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The cause of BPH is not well understood. No definite information
on risk factors exists. For centuries, it has been known that BPH
occurs mainly in older men and that it doesn't develop in men whose
testes were removed before puberty. For this reason, some
researchers believe that factors related to aging and the testes may
spur the development of BPH.
Throughout their lives, men produce both testosterone, an
important male hormone, and small amounts of estrogen, a female
hormone. As men age, the amount of active testosterone in the blood
decreases, leaving a higher proportion of estrogen. Studies done
with animals have suggested that BPH may occur because the higher
amount of estrogen within the gland increases the activity of
substances that promote cell growth.
Another theory focuses on dihydrotestosterone (DHT), a substance
derived from testosterone in the prostate, which may help control
its growth. Most animals lose their ability to produce DHT as they
age. However, some research has indicated that even with a drop in
the blood's testosterone level, older men continue to produce and
accumulate high levels of DHT in the prostate. This accumulation of
DHT may encourage the growth of cells. Scientists have also noted
that men who do not produce DHT do not develop BPH.
Some researchers suggest that BPH may develop as a result of
"instructions" given to cells early in life. According to this
theory, BPH occurs because cells in one section of the gland follow
these instructions and "reawaken" later in life. These "reawakened"
cells then deliver signals to other cells in the gland, instructing
them to grow or making them more sensitive to hormones that
influence growth.
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Many symptoms of BPH stem from obstruction of the urethra and
gradual loss of bladder function, which results in incomplete
emptying of the bladder. The symptoms of BPH vary, but the most
common ones involve changes or problems with urination, such as
- a hesitant, interrupted, weak stream
- urgency and leaking or dribbling
- more frequent urination, especially at night
The size of the prostate does not always determine how severe the
obstruction or the symptoms will be. Some men with greatly enlarged
glands have little obstruction and few symptoms while others, whose
glands are less enlarged, have more blockage and greater
problems.
Sometimes a man may not know he has any obstruction until he
suddenly finds himself unable to urinate at all. This condition,
called acute urinary retention, may be triggered by taking
over-the-counter cold or allergy medicines. Such medicines contain a
decongestant drug, known as a sympathomimetic. A potential side
effect of this drug may be to prevent the bladder opening from
relaxing and allowing urine to empty. When partial obstruction is
present, urinary retention also can be brought on by alcohol, cold
temperatures, or a long period of immobility.
It is important to tell your doctor about urinary problems such
as those described above. In 8 out of 10 cases, these symptoms
suggest BPH, but they also can signal other, more serious conditions
that require prompt treatment. These conditions, including prostate
cancer, can be ruled out only by a doctor's exam.
Severe BPH can cause serious problems over time. Urine retention
and strain on the bladder can lead to urinary tract infections,
bladder or kidney damage, bladder stones, and incontinence. If the
bladder is permanently damaged, treatment for BPH may be
ineffective. When BPH is found in its earlier stages, there is a
lower risk of developing such complications.
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You may first notice symptoms of BPH yourself, or your doctor may
find that your prostate is enlarged during a routine checkup. When
BPH is suspected, you may be referred to a urologist, a doctor who
specializes in problems of the urinary tract and the male
reproductive system. Several tests help the doctor identify the
problem and decide whether surgery is needed. The tests vary from
patient to patient, but the following are the most common.
This exam is usually the first test done. The doctor inserts a
gloved finger into the rectum and feels the part of the prostate
next to the rectum. This exam gives the doctor a general idea of the
size and condition of the gland.
To rule out cancer as a cause of urinary symptoms, your doctor
may recommend a PSA blood test. PSA, a protein produced by prostate
cells, is frequently present at elevated levels in the blood of men
who have prostate cancer. The U.S. Food and Drug Administration has
approved a PSA test for use in conjunction with a digital rectal
exam to help detect prostate cancer in men age 50 or older and for
monitoring prostate cancer patients after treatment. However, much
remains unknown about the interpretation of PSA levels, the test's
ability to discriminate cancer from benign prostate conditions, and
the best course of action following a finding of elevated PSA.
If there is a suspicion of prostate cancer, your doctor may
recommend a test with rectal ultrasound. In this procedure, a probe
inserted in the rectum directs sound waves at the prostate. The echo
patterns of the sound waves form an image of the prostate gland on a
display screen.
Sometimes the doctor will ask a patient to urinate into a special
device that measures how quickly the urine is flowing. A reduced
flow often suggests BPH.
In this exam, the doctor inserts a small tube through the opening
of the urethra in the penis. This procedure is done after a solution
numbs the inside of the penis so all sensation is lost. The tube,
called a cystoscope, contains a lens and a light system, which help
the doctor see the inside of the urethra and the bladder. This test
allows the doctor to determine the size of the gland and identify
the location and degree of the obstruction.
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Men who have BPH with symptoms usually need some kind of
treatment at some time. However, a number of recent studies have
questioned the need for early treatment when the gland is just
mildly enlarged. These studies report that early treatment may not
be needed because the symptoms of BPH clear up without treatment in
as many as one-third of all mild cases. Instead of immediate
treatment, they suggest regular checkups to watch for early
problems. If the condition begins to pose a danger to the patient's
health or causes a major inconvenience to him, treatment is usually
recommended.
Since BPH may cause urinary tract infections, a doctor will
usually clear up any infection with antibiotics before treating the
BPH itself. Although the need for treatment is not usually urgent,
doctors generally advise going ahead with treatment once the
problems become bothersome or present a health risk.
The following section describes the types of treatment that are
most commonly used for BPH.
Over the years, researchers have tried to find a way to shrink or
at least stop the growth of the prostate without using surgery. The
Food and Drug Administration (FDA) has approved four drugs to
relieve common symptoms associated with an enlarged prostate.
Finasteride, FDA-approved in 1992 (marketed under the name
Proscar), and dutasteride, FDA-approved in 2001 (marketed as
Avodart), inhibit production of the hormone DHT, which is involved
with prostate enlargement. The use of either of these drugs can
either prevent progression of growth of the prostate or actually
shrink the prostate in some men.
FDA also approved the drugs terazosin (marketed as Hytrin) in
1993, doxazosin (marketed as Cardura) in 1995, tamsulosin (marketed
as Flomax) in 1997, and alfuzosin (marketed as Uroxatral) in 2003
for the treatment of BPH. All four drugs act by relaxing the smooth
muscle of the prostate and bladder neck to improve urine flow and to
reduce bladder outlet obstruction. The four drugs belong to the
class known as alpha blockers. Terazosin and doxazosin were
developed first to treat high blood pressure. Tamsulosin and
alfuzosin were developed specifically to treat BPH.
NIDDK's Medical Therapy of Prostatic Symptoms (MTOPS) Trial
recently found that using finasteride and doxazosin together is more
effective than either drug alone to relieve symptoms and prevent BPH
progression. The two-drug regimen reduced the risk of BPH
progression by 67 percent, compared to 39 percent for doxazosin
alone and 34 percent for finasteride alone.
Because drug treatment is not effective in all cases, researchers
in recent years have developed a number of procedures that relieve
BPH symptoms but are less invasive than conventional surgery.
Transurethral microwave procedures. In May 1996, FDA
approved the Prostatron, a device that uses microwaves to heat and
destroy excess prostate tissue. In the procedure called
transurethral microwave thermotherapy (TUMT), the Prostatron sends
computer-regulated microwaves through a catheter to heat selected
portions of the prostate to at least 111 degrees Fahrenheit. A
cooling system protects the urinary tract during the procedure.
A similar microwave device, the Targis System, received FDA
approval in September 1997. Like the Prostatron, the Targis System
delivers microwaves to destroy selected portions of the prostate and
uses a cooling system to protect the urethra. A heat-sensing device
inserted in the rectum helps monitor the therapy.
Both procedures take about 1 hour and can be performed on an
outpatient basis without general anesthesia. Neither procedure has
been reported to lead to impotence or incontinence.
Although microwave therapy does not cure BPH, it reduces urinary
frequency, urgency, straining, and intermittent flow. It does not
correct the problem of incomplete emptying of the bladder. Ongoing
research will determine any long-term effects of microwave therapy
and who might benefit most from this therapy.
Transurethral needle ablation. In October 1996, FDA
approved Vidamed's minimally invasive Transurethral Needle Ablation
(TUNA) System for the treatment of BPH.
The TUNA System delivers low-level radiofrequency energy through
twin needles to burn away a well-defined region of the enlarged
prostate. Shields protect the urethra from heat damage. The TUNA
System improves urine flow and relieves symptoms with fewer side
effects when compared with transurethral resection of the prostate
(TURP). No incontinence or impotence has been observed.
Most doctors recommend removal of the enlarged part of the
prostate as the best long-term solution for patients with BPH. With
surgery for BPH, only the enlarged tissue that is pressing against
the urethra is removed; the rest of the inside tissue and the
outside capsule are left intact. Surgery usually relieves the
obstruction and incomplete emptying caused by BPH. The following
section describes the types of surgery that are used.
Transurethral surgery. In this type of surgery, no
external incision is needed. After giving anesthesia, the surgeon
reaches the prostate by inserting an instrument through the
urethra.
A procedure called TURP (transurethral resection of the prostate)
is used for 90 percent of all prostate surgeries done for BPH. With
TURP, an instrument called a resectoscope is inserted through the
penis. The resectoscope, which is about 12 inches long and 1/2 inch
in diameter, contains a light, valves for controlling irrigating
fluid, and an electrical loop that cuts tissue and seals blood
vessels.
During the 90-minute operation, the surgeon uses the
resectoscope's wire loop to remove the obstructing tissue one piece
at a time. The pieces of tissue are carried by the fluid into the
bladder and then flushed out at the end of the operation.
Most doctors suggest using TURP whenever possible. Transurethral
procedures are less traumatic than open forms of surgery and require
a shorter recovery period.
Another surgical procedure is called transurethral incision of
the prostate (TUIP). Instead of removing tissue, as with TURP, this
procedure widens the urethra by making a few small cuts in the
bladder neck, where the urethra joins the bladder, and in the
prostate gland itself. Although some people believe that TUIP gives
the same relief as TURP with less risk of side effects such as
retrograde ejaculation, its advantages and long-term side effects
have not been clearly established.
Open surgery. In the few cases when a transurethral
procedure cannot be used, open surgery, which requires an external
incision, may be used. Open surgery is often done when the gland is
greatly enlarged, when there are complicating factors, or when the
bladder has been damaged and needs to be repaired. The location of
the enlargement within the gland and the patient's general health
help the surgeon decide which of the three open procedures to
use.
With all the open procedures, anesthesia is given and an incision
is made. Once the surgeon reaches the prostate capsule, he scoops
out the enlarged tissue from inside the gland.
Laser surgery. In March 1996, FDA approved a surgical
procedure that employs side-firing laser fibers and Nd: YAG lasers
to vaporize obstructing prostate tissue. The doctor passes the laser
fiber through the urethra into the prostate using a cystoscope and
then delivers several bursts of energy lasting 30 to 60 seconds. The
laser energy destroys prostate tissue and causes shrinkage. Like
TURP, laser surgery requires anesthesia and a hospital stay. One
advantage of laser surgery over TURP is that laser surgery causes
little blood loss. Laser surgery also allows for a quicker recovery
time. But laser surgery may not be effective on larger prostates.
The long-term effectiveness of laser surgery is not known.
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If you have surgery, you'll probably stay in the hospital
depending on the type of surgery you had and how quickly you
recover.
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Foley catheter |
At the end of surgery, a special catheter is inserted through the
opening of the penis to drain urine from the bladder into a
collection bag. Called a Foley catheter, this device has a
water-filled balloon on the end that is placed in the bladder, which
keeps it in place.
This catheter is usually left in place for several days.
Sometimes, the catheter causes recurring painful bladder spasms the
day after surgery. These may be difficult to control, but they will
eventually disappear.
You may also be given antibiotics while you are in the hospital.
Many doctors start giving this medicine before or soon after surgery
to prevent infection. However, some recent studies suggest that
antibiotics may not be needed in every case, and your doctor may
prefer to wait until an infection is present to give them.
After surgery, you will probably notice some blood or clots in
your urine as the wound starts to heal. If your bladder is being
irrigated (flushed with water), you may notice that your urine
becomes red once the irrigation is stopped. Some bleeding is normal,
and it should clear up by the time you leave the hospital. During
your recovery, it is important to drink a lot of water (up to 8 cups
a day) to help flush out the bladder and speed healing.
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Take it easy the first few weeks after you get home. You may not
have any pain, but you still have an incision that is healing--even
with transurethral surgery, where the incision can't be seen. Since
many people try to do too much at the beginning and then have a
setback, it is a good idea to talk to your doctor before resuming
your normal routine. During this initial period of recovery at home,
avoid any straining or sudden movements that could tear the
incision. Here are some guidelines:
- Continue drinking a lot of water to flush the bladder.
- Avoid straining when moving your bowel.
- Eat a balanced diet to prevent constipation. If constipation
occurs, ask your doctor if you can take a laxative.
- Don't do any heavy lifting.
- Don't drive or operate machinery.
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Even though you should feel much better by the time you leave the
hospital, it will probably take a couple of months for you to heal
completely. During the recovery period, the following are some
common problems that can occur.
You may notice that your urinary stream is stronger right after
surgery, but it may take awhile before you can urinate completely
normally again. After the catheter is removed, urine will pass over
the surgical wound on the prostate, and you may initially have some
discomfort or feel a sense of urgency when you urinate. This problem
will gradually lessen, though, and after a couple of months you
should be able to urinate less frequently and more easily.
As the bladder returns to normal, you may have some temporary
problems controlling urination, but long-term incontinence rarely
occurs. Doctors find that the longer problems existed before
surgery, the longer it will take for the bladder to regain its full
function after the operation.
In the first few weeks after transurethral surgery, the scab
inside the bladder may loosen, and blood may suddenly appear in the
urine. Although this can be alarming, the bleeding usually stops
with a short period of resting in bed and drinking fluids. However,
if your urine is so red that it is difficult to see through or if it
contains clots or if you feel any discomfort, be sure to contact
your doctor.
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Many men worry about whether surgery for BPH will affect their
ability to enjoy sex. Some sources state that sexual function is
rarely affected, while others claim that it can cause problems in up
to 30 percent of all cases. However, most doctors say that even
though it takes awhile for sexual function to return fully, with
time, most men are able to enjoy sex again.
Complete recovery of sexual function may take up to 1 year,
lagging behind a person's general recovery. The exact length of time
depends on how long after symptoms appeared that BPH surgery was
done and on the type of surgery. Following is a summary of how
surgery is likely to affect the following aspects of sexual
function.
Most doctors agree that if you were able to maintain an erection
shortly before surgery, you will probably be able to have erections
afterward. Surgery rarely causes a loss of erectile function.
However, surgery cannot usually restore function that was lost
before the operation.
Although most men are able to continue having erections after
surgery, a prostatectomy frequently makes them sterile (unable to
father children) by causing a condition called "retrograde
ejaculation" or "dry climax."
During sexual activity, sperm from the testes enters the urethra
near the opening of the bladder. Normally, a muscle blocks off the
entrance to the bladder, and the semen is expelled through the
penis. However, the coring action of prostate surgery cuts this
muscle as it widens the neck of the bladder. Following surgery, the
semen takes the path of least resistance and enters the wider
opening to the bladder rather than being expelled through the penis.
Later it is harmlessly flushed out with urine. In some cases, this
condition can be treated with a drug called pseudoephedrine, found
in many cold medicines, or imipramine. These drugs improve muscle
tone at the bladder neck and keep semen from entering the
bladder.
Most men find little or no difference in the sensation of orgasm,
or sexual climax, before and after surgery. Although it may take
some time to get used to retrograde ejaculation, you should
eventually find sex as pleasurable after surgery as before.
Many people have found that concerns about sexual function can
interfere with sex as much as the operation itself. Understanding
the surgical procedure and talking over any worries with the doctor
before surgery often help men regain sexual function earlier. Many
men also find it helpful to talk to a counselor during the
adjustment period after surgery.
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In the years after your surgery, it is important to continue
having a rectal exam once a year and to have any symptoms checked by
your doctor.
Since surgery for BPH leaves behind a good part of the gland, it
is still possible for prostate problems, including BPH, to develop
again. However, surgery usually offers relief from BPH for at least
15 years. Only 10 percent of the men who have surgery for BPH
eventually need a second operation for enlargement. Usually these
are men who had the first surgery at an early age.
Sometimes, scar tissue resulting from surgery requires treatment
in the year after surgery. Rarely, the opening of the bladder
becomes scarred and shrinks, causing obstruction. This problem may
require a surgical procedure similar to transurethral incision. More often, scar tissue may form in the urethra and
cause narrowing. This problem can usually be solved during an office
visit when the doctor stretches the urethra.
Stents are small devices inserted through the urethra to the
narrowed area and allowed to expand, like a spring. The stent pushes
back the prostatic tissue, widening the urethra. FDA approved the
Urolume Endoprosthesis in 1996 to relieve urinary obstruction in men
and improve the ability to urinate. The device is approved for use
in men for whom other standard surgical procedures to correct
urinary obstruction have failed.
Although some of the signs of BPH and prostate cancer are the
same, having BPH does not seem to increase the chances of getting
prostate cancer. Nevertheless, a man who has BPH may have undetected
prostate cancer at the same time or may develop prostate cancer in
the future. For this reason, the National Cancer Institute and the
American Cancer Society recommend that all men over 40 have a rectal
exam once a year to screen for prostate cancer.
After BPH surgery, the tissue removed is routinely checked for
hidden cancer cells. In about 1 out of 10 cases, some cancer tissue
is found, but often it is limited to a few cells of a nonaggressive
type of cancer, and no treatment is needed.
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The National Institute of Diabetes and Digestive and Kidney
Diseases (NIDDK) was established by Congress in 1950 as one of the
National Institutes of Health (NIH), whose mission is to improve
human health through biomedical research. NIH is the research branch
of the U.S. Department of Health and Human Services.
NIDDK conducts and supports a variety of research in diseases of the kidney
and urinary tract. Much of the research targets disorders of the lower urinary
tract, including BPH, urinary tract infection, interstitial cystitis, urinary
obstruction, prostatitis, and urinary stones. The knowledge gained from these
studies is advancing scientific understanding of why BPH develops and may
lead to improved methods of diagnosing and treating prostate enlargement.
One such study was the MTOPS Trial, which recently ended. The results are
summarized above under Drug Treatment.
The Minimally Invasive Surgical Therapies (MIST) treatment group is looking
at TUMT, TUNA, and other transurethral treatments for BPH that do not require
a hospital stay.
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Anesthesia: A substance that prevents pain from being
felt, given before an operation.
Anus: The opening of the rectum where solid waste leaves
the body.
Bladder: The muscular bag in the lower abdomen where urine
is stored.
Catheter: A tube inserted through the penis to the bladder
in order to drain urine from the body.
Cystoscope: A tube-like instrument used to view the
interior of the bladder.
Ejaculation: Discharging semen from the penis during
sexual climax.
Gland: An organ that makes and releases substances to
other parts of the body.
Hormone: A substance that stimulates the function of a
gland.
Impotent: Unable to have an erection.
Incontinence: The inability to control urination.
Obstruction: A clog or blockage that prevents liquid from
flowing easily.
Perineum: The area between the scrotum and the anus.
Rectum: The last part of the large intestine (colon)
ending in the anus.
Reproductive system: The bodily systems that allow men and
women to have children.
Retropubic: Behind the pubic bone.
Scrotum: The sac of skin that contains the testes.
Semen: The fluid, containing sperm, which comes out of the
penis during sexual excitement.
Sterile: Unable to father children.
Suprapubic: Above the pubic bone.
Testes: The male reproductive glands where sperm are
produced.
Ultrasound: A type of test in which sound waves too high
to hear are aimed at a structure to produce an image of it.
Urinary tract: The path that urine takes as it leaves the
body. It includes the kidneys, ureters, bladder, and urethra.
Urination: Discharge of liquid waste from the body.
Urethra: The canal inside the penis that urine passes
through as it leaves the body.
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