Prostate enlargement
Prostate enlargement, medically referred to as benign prostatic hyperplasia (BPH), is a common condition that affects many men as they age, particularly starting around the age of fifty. It involves the enlargement of the prostate gland, which can lead to various urinary issues due to its location surrounding the urethra. Symptoms often include difficulties with urination, such as weak stream, frequent urination, and bladder irritation, which can significantly impact quality of life. While the exact causes of BPH remain unclear, factors such as hormonal changes, genetics, and cell growth are believed to play a role. Treatment options range from watchful waiting for mild symptoms to medication and surgical interventions for more severe cases. Medications might include alpha-blockers and 5-alpha-reductase inhibitors, while surgical options can entail procedures like transurethral resection of the prostate (TURP). Ongoing research continues to explore the mechanisms behind BPH and potential new therapies, including combination treatments and alternative remedies. Understanding this condition is crucial for those affected and seeking effective management strategies.
Prostate enlargement
ALSO KNOWN AS: Benign prostatic hyperplasia or hypertrophy (BPH)
ANATOMY OR SYSTEM AFFECTED: Reproductive system, urinary system
DEFINITION: A common condition in which the prostate gland enlarges as a man matures
CAUSES: Unknown; factors include hormones (estrogen, androgens), cell growth, genetics
SYMPTOMS: Constriction of urethra and bladder irritation resulting in urination problems (voiding hesitancy, intermittency, weak stream, dribbling, straining, frequency, infections)
DURATION: Chronic
TREATMENTS: None (watchful waiting), medications (alpha-blockers, enzyme inhibitors of 5-alpha-reductase, herbal remedies), surgery to remove tissue or gland
Causes and Symptoms
Prostate enlargement is also known as benign prostatic hyperplasia or (BPH). Benign refers to the nonmalignant nature of the condition. The prostate gland is a walnut-sized organ located below the bladder, the organ in which urine is stored. The prostate surrounds part of the urethra, which is a long tube that transports urine from the to the outside of the body. The gland has a role in both the male reproductive system and the urinary system. The prostate adds secretions to semen, an alkaline that neutralizes the acidic environment of the female and provides nutritional elements for the sperm. BPH symptoms occur in more than half of men in their sixties and more than 90 percent of men in their eighties.
Prostate enlargement begins to develop in men at around age fifty. No single factor fully explains the condition, but many factors are known to be involved in BPH, including hormones, cell growth, and genetics. The hormones involved are the female hormone and the male hormones (androgens) testosterone and dihydrotestosterone (DHT). Men produce and a small amount of estrogen throughout their lives. The testosterone level decreases as men age and the relative amount of estrogen increases. Scientists have shown that the addition of estrogen to androgen increases BPH development in animals and that there is an increased ratio of female to male hormone (estrogen/androgen ratio) in prostatic tissue with BPH. DHT is another androgen that is related to BPH. It has been shown that men who do not have the enzyme (protein) that converts testosterone to DHT have small-sized prostate glands throughout their lives. Older men continue to produce DHT in the prostate, and this hormone may affect cell growth in the prostate. Moreover, studies have shown that BPH occurs in many men with a positive family history for prostate enlargement.
The is surrounded by a tissue lining called the capsule. As the prostate enlarges against its surrounding capsule, the whole structure presses against that part of the that the prostate surrounds; this constricts (obstructs) the urethra and affects the bladder. The bladder wall thickens and becomes more irritable. The symptoms of BPH result from the urethral and resulting bladder irritation and functional decline. Urethral obstruction causes voiding hesitancy, intermittency, weak stream, dribbling, and straining. Bladder irritation causes more to smaller amounts of urine, resulting in more frequent urination, especially at night. Eventually, the bladder may weaken and its function may be affected adversely. The bladder can lose its ability to completely empty the stored urine during voiding; this can lead to acute urinary retention in the bladder.
Treatment and Therapy
The patient may notice the symptoms of BPH first and schedule an appointment with his doctor for evaluation. BPH diagnostic includes a number of steps. A detailed medical history, focusing on the symptoms of the urinary system, will be obtained. A questionnaire such as the American Urological Association Symptom Index will help the doctor decide the severity of the symptoms. A will be performed, including a digital rectal examination, in which a gloved finger is inserted into the to evaluate the size and condition of the prostate. A urine test to check for blood or signs of urine infection and a blood test to evaluate whether the are affected will be done as well.
Other tests may be recommended to determine if the symptoms are associated with the bladder or kidney or if cancer is present. One such test, postvoid residual urine volume, measures how much urine is left in the bladder after urination. The two tests that can determine the degree of blockage in urine flow are uroflowmetry, which measures the rate and amount of urine passed, and pressure-flow studies, which assess bladder pressure during voiding. In some cases, imaging of the kidney, bladder, and prostate may be necessary with x-rays, ultrasound, or cystoscopy, in which an instrument is passed through the urethra and used to view the interior of the bladder. A test for prostate-specific (PSA) may also be recommended. PSA is a protein that is produced by prostate cells; it is often elevated in patients with prostate cancer but may also be increased in BPH.
Treatment of BPH includes conservative measures (watchful waiting), medical options (both conventional and alternative), surgical procedures, and minimally invasive therapies. The patient’s decision is usually based on the effects of the BPH symptoms on his quality of life and on weighing the risks and benefits of available interventions. If the symptoms are severe and the urinary or reproductive tract is affected, however, then BPH needs to be treated.
BPH symptoms that do not bother the patient can be managed with watchful waiting. There is no active treatment involved, and the patient will see his doctor at least once a year to determine whether the symptoms are staying the same, improving, or worsening.
Medical options include taking conventional drugs such as an alpha-blocker or enzyme inhibitors of 5-alpha-reductase. Alpha-blockers relax the smooth muscles of the bladder neck and prostate. Examples of alpha-blockers include terazosin (Hytrin), doxazosin (Cardura), tamsulosin (Flomax), and alfuzosin (Uroxatral). The side effects of these drugs include dizziness, fainting, headache, tiredness, and low blood pressure. Enzyme inhibitors of 5-alpha-reductase prevent the conversion of testosterone to DHT, which in turn can decrease prostate growth. There are two drugs approved by the Food and Drug Administration (FDA) in this category, finasteride (Proscar) and dutasteride (Avodart). Their side effects include decreased libido, ejaculatory problems, and erectile dysfunction.
Alternative medications consist of herbal remedies. Studies on saw palmetto, a fruit extract from the American dwarf palm tree, have yielded equivocal results on its as a BPH treatment. Systematic reviews of beta-sitosterol plant extract, cernilton from rye grass pollen, and Pygeum bark extract from African plum tree showed that there is some BPH symptomatic improvement with these supplements. Better-designed studies for these remedies, however, may not confirm this result, as was seen in the case of saw palmetto.
Surgical management of BPH includes transurethral resection of the prostate (TURP), transurethral incision of the prostate (TUIP), open surgery (prostatectomy), and laser surgery. TURP is the most common surgical option; the surgeon uses an instrument called a resectoscope to remove enlarged prostate tissue through the urethra. TUIP usually involves placing two deep incisions in the prostate where it meets the bladder neck; this decreases the resistance to urine flow from the bladder. Prostate tissue is not removed in this procedure. Prostatectomy, or prostate gland removal, is done in some cases; this involves removing the enlarged prostate in an open surgery. Laser surgery vaporizes the prostate tissue causing obstruction.
Minimally invasive procedures for treatment of BPH symptoms include application of heat from various sources to eliminate excessive prostatic tissue, such as transurethral needle ablation of the prostate (TUNA), transurethral microwave thermotherapy (TUMT), transurethral vaporization of the prostate (TUVP), water-induced thermotherapy, high-intensity ultrasound energy therapy, and laser coagulation. Removal of obstructing prostate tissue by these methods can allow better urinary flow. Mechanical approaches such as balloon and urethral stent placement dilate the obstructed area of the urethra. Balloon dilation involves placing a with a balloon at its tip through the urethra; the balloon is inflated in the area of obstruction. Urethral are placed in the obstructed urethral area to dilate the narrowed section for better urinary flow.
As with medical treatments, surgical management and minimally invasive procedures have risks and benefits. The risks include bleeding, infection, and impotence. The best therapy for BPH is not the same for all patients. The treatment options will depend on the severity of symptoms, the risks and benefits of the therapy, and the general health condition of the patient. A satisfactory management plan to treat BPH symptoms can be accomplished in a partnership between the patient and his physician.
Perspective and Prospects
The development of prostate enlargement is multifactorial, and the specific steps involved in its progression are still unresolved. Research studies are ongoing to evaluate the processes involved in the development of this condition. For example, chronic has been implicated in BPH. Studies have shown that tissue specimens from enlarged prostates have pro-inflammatory cells and cytokines. One implicated in BPH development is transforming growth factor beta. TGF-beta is involved in the cell signaling that causes an increase in expression of some genes in BPH, such as the gene called GAGEC1. This gene is a member of the GAGE family. The proteins expressed by these genes are associated with male and female reproductive organs such as the prostate, testis, Fallopian tubes, uterus, and placenta, as well as in cancers of the prostate, testis, and uterus. Unraveling these molecular processes in BPH may lead to the design of new therapeutic modalities for an enlarged prostate.
Recently, studies evaluating combination therapy, such as using both an alpha-blocker and a 5-alpha-reductase inhibitor for treatment of BPH and its related symptoms, have been carried out. One such study is the Medical Therapy of Prostate Symptoms Study (MTOPS), which showed that the clinical progression of BPH is delayed and symptoms are reduced by combination therapy. Clinical guidelines from authoritative sources such as the American Urological Association, the Agency for Healthcare Research and Quality, and the International Consultation on BPH still recommend that a patient discuss the risks and benefits of combination therapy with his physician. For example, the risks of side effects from two medications and the economic burden of purchasing two medications should be balanced with the benefits derived from the combination therapy.
The search for novel drugs to treat an enlarged prostate continues, including the development of more selective alpha-blockers and 5-alpha-reductase inhibitors (both steroidal and nonsteroidal). The factors that are involved in the development of BPH, such as cytokines, growth factors, estrogen, and androgen hormone receptors, are being evaluated as targets for potential therapeutic options. Some studies have also shown that botulinum neurotoxin (Botox) injection can shrink the prostate and reduce levels of PSA. However, such use of Botox is off-label and currently not approved for BPH by the FDA. Significant basic research regarding the mechanisms by which Botox affects the prostate and evidence-based data for use of Botox in BPH are needed.
Current studies in managing an enlarged prostate also include evaluation of specific aspects of herbal preparations such as saw palmetto and other alternative phytomedicine products. Moreover, treatment of BPH by surgical and minimally invasive procedures are still being compared with regard to clinical efficacy, related complications, and optimal energy sources for heat. The future will certainly bring more answers about the biological basis of enlarged prostate as well as even better treatment options.
Bibliography
"Benign Prostatic Hyperplasia (BPH)." Mayo Clinic, 21 Feb. 2023, www.mayoclinic.org/diseases-conditions/benign-prostatic-hyperplasia/symptoms-causes/syc-20370087. Accessed 7 Aug. 2023.
Chuang, Yao-Chi, and Michael B. Chancellor. “The Application of Botulinum Toxin in the Prostate.” Journal of Urology 176, no. 6 (December, 2006): 2375–2382.
DiPaola, Robert S., and Ronald A. Morton. “Proven and Unproven Therapy for Benign Prostatic Hyperplasia.” New England Journal of Medicine 354, no. 6 (February 9, 2006): 632–634.
"Enlarged Prostate." MedlinePlus, 15 Dec. 2023, medlineplus.gov/enlargedprostatebph.html. Accessed 8 Apr. 2024.
Komaroff, Anthony, ed. “Prostate Gland.” In Harvard Medical School Family Health Guide. New York: Free Press, 2005.
McVary, Kevin T., ed. Management of Benign Prostatic Hypertrophy. Totowa, N.J.: Humana Press, 2004.
Porto, Joao G., et al. "Minimally Invasive Techniques in Quest of Holy Grail of Surgical Management of Enlarged Prostates: A Narrative Review." World Journal of Urology, vol. 42, 2024. DOI: 10.1007/s00345-023-04747-8. Accessed 8 Apr. 2024.
“Prostate Disorders.” In The Merck Manual Home Health Handbook, edited by Robert S. Porter, et al. Whitehouse Station, N.J.: Merck Research Laboratories, 2009.
"Prostate Enlargement: Benign Prostatic Hyperplasia." National Kidney and Urologic Diseases Information Clearinghouse, March 23, 2012.
Rous, Stephen N. The Prostate Book: Sound Advice on Symptoms and Treatment. 3d ed. New York: W. W. Norton, 2002.