Causes, Diagnosis and Treatment of Benign Prostatic Hyperplasia
Benign prostatic hyperplasia (BPH) is, as its name suggests, a noncancerous enlargement of the prostate gland common among men during middle and old age. The prostate is a walnut-sized gland located in the pelvis needed to supply the fluid that nourishes sperm and helps to transport it through the urethra during sexual ejaculation.
As men age, the prostate gland usually grows in size and may start pressing against the urethra, obstructing urine flow. Over time, this may cause the bladder to become thickened, irritated and overly sensitized, resulting in frequent urination even when small amounts of urine are present. Eventually, the bladder can lose its ability to empty completely. Recognizing benign prostatic hyperplasia in its early stages can lower the risk of developing complications such as incontinence, urinary tract infections, bladder or kidney damage and bladder stones.
Paradoxically, the severity of symptoms of BPH does not always correlate with the size of the prostate. Some patients with small prostates can have serious symptoms, whereas others with large prostates may have no symptoms at all.
Causes of Benign Prostatic Hyperplasia
Benign prostatic hyperplasia is a result of the natural growth of the prostate gland. During a man’s lifetime, the prostate gland undergoes two periods of growth. Early in puberty, it doubles in size. Then, beginning around age 25, the prostate gland gradually starts growing again. It is during this second growth period that men develop benign prostatic hyperplasia.
Age is the primary risk factor associated with benign prostatic hyperplasia while heredity also plays a role. While it is rare to experience symptoms of BPH before age 40, the condition affects nearly half of all men in their 60s and 90% of men over age 80. A family history of benign prostatic hyperplasia increases the risk of developing this condition. BPH is more common in white Caucasians than in Asian men. Despite common belief, there does not seem to be a link between sexual activity and incidence of prostate enlargement.
It is not exactly known what causes benign prostatic hyperplasia. One theory has it that it is due to changes in hormonal balance between testosterone and estrogen as men age and the amount of testosterone production decreases. These changes may in turn promote cell growth in the prostate. But another theory suggests just the opposite, linking prostate growth to hormonal substance derived from testosterone called dihydrotestosterone (DHT, which is also responsible for androgenetic alopecia). It has been observed that men who had their testicles removed at a young age (testicles produce testosterone and DHT is its metabolite), do not experience enlargement of the prostate.
Symptoms of Benign Prostatic Hyperplasia
Having an enlarged prostate does not automatically imply that you have symptoms. More than half of all patients with BPH do not experience any symptoms. When symptoms do occur, they usually result from the obstruction of the urethra, causing the loss of bladder function and problems with urination, such as weak or interrupted urine stream or leaking and dribbling urine. Other symptoms of benign prostatic hyperplasia include increased urgency to urinate or more frequent urination, especially at night. Some patients may also experience pain or bleeding during urination while others may develop pelvic pain or experience sexual pain during ejaculation.
In rare cases, no symptoms will be felt until a man is suddenly unable to urinate at all. This is an emergency condition called acute urinary retention and may be triggered by use of certain medications that contain a decongestant which prevents the opening of the bladder. Other triggers may include cold temperatures, long periods of immobility and alcohol. This acute condition requires immediate medical attention to prevent permanent damage. It can be relieved by placing a urethral catheter.
Diagnosing Benign Prostatic Hyperplasia
Some men with benign prostatic hyperplasia notice symptoms themselves and schedule an appointment with their doctor while others learn about their suspected condition after a routine physical examination. If benign prostatic hyperplasia or another urological condition is suspected, the patient is referred to a urologist. Several tests can be used to help diagnose BPH, including:
Questionnaire. The pain assessment form can help the doctor to determine the severity of the condition.
Digital rectal examination. The doctor inserts a gloved, lubricated finger in the patient’s rectum to determine the size and firmness of the prostate.
Prostate specific antigen (PSA) test. This test measures levels of PSA (a protein produced by prostate cells) in the blood. Prostate cancer and prostatitis can also elevate PSA and produce symptoms similar to those of BPH. The blood test will also be used to measure the level of creatinine to determine how well the kidneys are working.
Urine analysis to detect a possible urinary tract infection or blood in the urine.
Postvoid residual volume test uses ultrasound to see how well the patient is able to empty his bladder during urination (in the past this test was done with a catheter inserted into the urethra).
Imaging tests. Ultrasound is typically used to check the size and structure of the bladder, prostate and kidneys. An x-ray of the urinary tract, called intravenous pyelography, may also be used to examine the function of the kidneys and the flow of urine to the bladder. Computer tomography (CT) scan is sometimes used to detect the blockage of the urethra and to check for an enlarged prostate.
Cystoscopy allows the urologist to see the inside of the urethra and the bladder and to determine the size of the prostate gland and assess the blockage of the urethra.
Urodynamic studies check internal bladder pressure to determine how effectively the bladder contracts.
Uroflowmetry measures how quickly urine is flowing as reduced flow may suggest the presence of BPH.
Biopsy. In rare cases the urologist may need to take a tissue sample from the prostate gland to verify the diagnosis of BPH and to rule out cancer.
Treatment of Benign Prostatic Hyperplasia
There is no ultimate cure for benign prostatic hyperplasia yet, so treatment focuses on relieving its symptoms. However, many experts believe that mild cases of BPH do not require any treatment, only monitoring, as symptoms may clear on their own. Several treatment options, including drugs, heat therapy and surgery, are available for moderate to severe cases of BPH when symptoms become a major inconvenience.
Two classes of drugs are used to treat symptoms of BPH:
Alpha blockers improve urine flow by relaxing the smooth muscle of the prostate and the neck of the bladder. These medications are probably better known for their use in the treatment of elevated blood pressure. Alfuzosin (Uroxatral), doxazosin (Cardura), silodosin (Rapaflo), tamsulosin (Flomax) and terazosin (Hytrin) are all approved to treat BPH. Potential side effects of alpha blockers include dizziness, weakness, drowsiness, runny nose, sleep difficulties and rarely also sexual problems or accelerated heartbeat.
5-alpha reductase inhibitors slow the prostate’s growth or even reduce its size by impeding production of dihydrotestosterone (DHT), a metabolite of the male hormone testosterone. Two 5-alpha reductase inhibitors have been approved to treat BPH, i.e. finasteride (Proscar) and dutasteride (Avodart). Their side effects may include difficulties with erections (often subsiding after the first year) and sometimes tenderness and enlargement of the breast (gynecomastia). Women may not take or even handle crushed tablets of 5-alpha reductase inhibitors because of the risk of a birth defect to their male fetus.
Medication combo. The combination of an alpha blocker and a 5-alpha reductase inhibitor was found to be more effective in treating the symptoms of BPH than either one alone.
There are several forms of minimally invasive heat therapy available to treat benign prostatic hyperplasia:
Transurethral microwave therapy (TUMT) uses heat in the form of microwaves to destroy excess prostate tissue.
Transurethral needle ablation (TUNA) uses heat in the form of low-level radiofrequency energy to burn a portion of the enlarged prostate.
Transurethral electro-vaporization of the prostate (TUEVAP) uses a high-frequency electrical current to remove excess prostate cells.
Transurethral evaporation of prostate (TUEP) is similar to the above, except that laser energy is substituted for electrical current.
Photoselective vaporization of the prostate (PVP) uses laser energy to melt away problematic tissue.
Holmium laser ablation of the prostate (HoLAP) is similar to the above method except that a different type of laser is used to dry up and destroy problematic prostate cells.
Holmium laser enucleation of the prostate (HoLEP) uses laser to cut and remove the excess prostate tissue.
Although the above procedures do not work well in patients with very large prostates, for those with moderate prostate enlargement, they reduce urinary urgency, frequency, straining and intermittent flow. However, in severe cases of BPH medications and heat therapy are not enough to relieve symptoms. If the patient experiences incontinence, urinary retention, recurrent blood in the urine or recurrent urinary tract infections, an operation may be necessary to treat benign prostatic hyperplasia.
Transurethral resection of the prostate (TURP) is the surgery most commonly used to treat benign prostatic hyperplasia. In this procedure, the surgeon removes obstructive tissue a small piece at a time with an instrument called a resectoscope inserted through the penis.
Transurethral incision of the prostate (TUIP) is a technique mostly used in patients who have a relatively small or only moderately enlarged prostate. It involves widening the urethra by making small incisions in the prostate gland.
Prostatectomy. In some cases, open surgery under general anesthesia may be required to remove the prostate gland. This procedure, called prostatectomy, involves making an incision in the abdomen or between the anus and genitals and removing the whole prostate gland. A prostatectomy is reserved for cases when the prostate is greatly enlarged, if there is bladder damage or cancer. A less invasive form of prostatectomy, called open simple prostatectomy, consists in removing only the portion of the prostate blocking urine flow.
The risks of prostate surgery include temporary or sometimes even permanent impotence, retrograde ejaculation, infertility, urinary incontinence and narrowing of the urethra. However, many patients continue to experience normal sexual function after prostate surgery.
Some men take herbal supplements or over-the-counter herbal pills specifically designed to treat enlarged prostates, containing extracts from saw palmetto and stinging nettle, beta-sitosterol or pumpkin seeds oil in an effort to control or prevent benign prostatic hyperplasia. However, patients are advised to consult their doctor before trying any alternative therapy.
Where to Find More Information: American Urological Association