What Is an Enlarged Prostate?
It is common for the prostate gland to become enlarged as a man ages. Doctors call the condition benign prostatic hyperplasia (
BPH), benign prostatic hypertrophy, or an enlarged prostate.
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. An enlarged prostate 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 irritated. 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, and urine remains in the bladder. Both 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 physicians for an enlarged prostate.
Understanding the Prostate
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. 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.
The cause of an enlarged prostate is not well understood. No definite information on risk factors for an enlarged prostate 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.
Symptoms of an Enlarged Prostate
Many symptoms of an enlarged prostate stem from obstruction of the urethra and gradual loss of bladder function, which results in incomplete emptying of the bladder. Symptoms 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.
You may first notice symptoms of an enlarged prostate yourself, or your doctor may find that your prostate is enlarged during a routine checkup. When an enlarged prostate 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:
- Digital Rectal Exam (DRE). This exam is usually the first test performed. 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.
- Prostate Specific Antigen (PSA) Blood Test. To rule out cancer as a cause of urinary symptoms, your doctor may recommend a PSA 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 distinguish cancer from benign prostate conditions, and the best course of action following a finding of elevated PSA.
- Rectal Ultrasound. 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.
- Urine Flow Study. 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.
- Cystoscopy. 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.
(Click Enlarged Prostate Diagnosis for more information.)
Men who have
BPH and
enlarged prostate symptoms will usually require some form of treatment at some point. However, a number of recent studies have questioned the need for early treatment when the gland is only mildly enlarged. These studies report that early treatment may not be needed because the symptoms of an enlarged prostrate clear up without treatment in as many as one third of all mild cases. Instead of immediate BPH treatment, these studies recommend 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 an enlarged prostate 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.
About half the men with an enlarged prostate eventually have symptoms that are bothersome enough to need treatment. An enlarged prostate cannot be cured, but drugs or surgery can often relieve its symptoms. Also, the symptoms of an enlarged prostate do not always grow worse.
There are three ways to manage an enlarged prostate:
- Watchful waiting (regular follow-up with your doctor)
- Drug therapy
- Surgery.
If you have an enlarged prostate, talk with your doctor about which type of treatment is the best choice for you. Your symptoms may change over time, so be sure to tell your doctor about any new changes.
Enlarged Prostate Statistics
About 9 percent of men 30 years of age and older (6.3 million men) self-reported having been told by a physician they had an enlarged prostate.
It is estimated that an enlarged prostate occurs in different age groups at the following rates:
- Ages 30-54: 2.2 percent
- Ages 55-74: 19.6 percent
- Ages 75 and up: 36.3 percent.
The estimated number of hospital discharges among men who are 20 years old or older with a discharge diagnosis of enlarged prostate includes:
- 402,000 discharges (2001)
- 398,000 discharges (2000).
The estimated number of doctor visits by men age 20 or older with enlarged prostate as a listed diagnosis includes:
- 6.4 million visits (2000)
- 6.0 million visits (1999).
