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| Prostate What is 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. The prostate also surrounds the urethra; the canal through which urine passes out of the body. Changes during the ageing process 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. 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. Then, at around the age of 25, the gland begins to grow again. This second growth phase often results, years later, in BPH. Although 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 the age of 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. 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, and urine then 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 both sexually and for urination. However, prostate enlargement is as common a part of aging as grey hair. As life expectancy rises, so does the occurrence of BPH. Why does BPH occur? The cause of BPH is not well understood. 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 dihydrotes-tosterone (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. BHP Symptoms 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:
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 is called Acute Urinary Retention, and 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 through examination by a doctor. 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. Back to top Diagnosis 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 specialises 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 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. Prostate Specific Antigen (PSA) Blood Test In order 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. 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. Tests are therefore ongoing, to address these issues. 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 which measures how quickly the urine is flowing. A reduced flow often suggests BPH. Intravenous Pyelogram (IVP) IVP is an x-ray of the urinary tract. In this test, a dye is injected into a vein, and the x-ray is taken. The dye makes the urine visible on the x-ray and shows any obstruction or blockage in the urinary tract. 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. Treatment 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 often 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 troublesome, or present a health risk. Back to top Drug Treatment Over the years, researchers have tried to find a way to shrink or at least stop the growth of the prostate without using surgery. Recently, several new medications have been tested in clinical trials, and the Food and Drug Administration (FDA) has approved four drugs to treat BPH. These drugs may relieve common symptoms associated with an enlarged prostate. Finasteride (marketed under the name Proscar), FDA-approved in 1992, inhibits production of the hormone DHT, which is involved with prostate enlargement. Its use can actually shrink the prostate in some men. FDA also approved the drugs terazosin (marketed as Hytrin) in 1993, doxazosin (marketed as Cardura) in 1995, and tamsulosin (marketed as Flomax) in 1997 for the treatment of BPH. All three drugs act by relaxing the smooth muscle of the prostate and bladder neck to improve urine flow and to reduce bladder outlet obstruction. Terazosin, doxazosin, and tamsulosin belong to the class of drugs known as alpha blockers. Terazosin and doxazosin were developed first to treat high blood pressure. Tamsulosin is the first alpha blocker developed specifically to treat BPH. Nonsurgical Treatment 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 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. While 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 radio frequency 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. Surgical Treatment 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. Back to top 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 or she 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 vaporise 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. Recovery after surgery If you have surgery, you'll probably stay in the hospital from 3 to 10 days depending on the type of surgery you had and how quickly you recover. 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. Back to top |
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