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Magill’s Medical Guide, 9th Edition

Prostate enlargement

by Joseph Muraca, , OMS-III

Category: Disease/Disorder

Also known as: Benign prostatic hyperplasia or hypertrophy (BPH)

Anatomy or system affected: Reproductive system, urinary system

Specialties and related fields: Endocrinology, urology

Definition: A common condition in which the prostate gland enlarges as a man matures.

Key terms:

benign: not recurrent or malignant; associated with favorable outcomes

cytokines: proteins that influence communication and interactions between cells; examples include interleukins, lymphokines, and cell-signaling molecules such as tumor necrosis factor, transforming growth factor, and interferons

endocrine: a term applied to organs or cells that produce hormones

enzyme: a protein that enhances the rate of chemical changes in living cells

gene: the basic unit of a chromosome carrying the information for a specific protein that is inherited

hormone: a chemical substance produced by an endocrine organ or cells that causes specific effects on the structure and function of the target organs or cells

inflammation: the body’s defensive response to injury or infection; includes many factors in the process, including white blood cells and cytokines

laser: an instrument that generates a small intense beam of light that is used in surgery and other medical procedures

malignant: having the features of uncontrolled growth, invasion, and spreading; associated with unfavorable outcomes

phytomedicine: the use of plant substances as alternative treatment for medical diseases and conditions

tissue: a group of similar cells with a specific function

transurethral: across or through the urethra

CAUSES AND SYMPTOMS

Prostate enlargement is also known as “benign prostatic hyperplasia”

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 bladder 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 fluid that neutralizes the acidic environment of the female reproductive system 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. The enlargement of the prostate gland can cause lower urinary tract symptoms (LUTS). LUTS is a term used to describe symptoms related to the bladder and urethra.

BPH becomes more prevalent as men age. Symptomatic BPH usually occurs after age forty-five. No single factor fully explains the condition, but many factors are known to be involved in BPH, including hormones, race, obesity, cell growth, and genetics. The hormones involved are the female hormone estrogen and the male hormones (androgens) testosterone and dihydrotestosterone (DHT).

Androgens are sex hormones that contribute to cell growth in the prostate gland and inhibit cell death. Men produce testosterone 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. Further, pre-pubertal males have lower levels of testosterone and DHT and BPH does not occur. Post-puberty, these hormones become elevated and BPH may eventually occur. It follows that those who have been castrated will have an inability to develop BPH. 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 prostate gland 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 urethra 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 obstruction and resulting bladder irritation and functional decline. These symptoms usually occur gradually and can worsen with time. Urethral obstruction causes voiding hesitancy, intermittency, weak stream, dribbling, and straining. Bladder irritation causes more sensitivity 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. However, many men with prostatic enlargement remain asymptomatic.

TREATMENT AND THERAPY

The patient may notice the symptoms of BPH first and schedule an appointment with his doctor for evaluation. BPH diagnostic assessment includes a number of steps. A history focused on evaluating storage symptoms, voiding symptoms and postvoiding symptoms will be obtained in order to determine the severity of BPH. A questionnaire such as the American Urological Association Symptom Index can help to further assess symptom severity and monitor response to treatments. A physical examination will be performed, including a digital rectal examination, in which a gloved finger is inserted into the rectum 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 kidneys are affected will be done as well. The patient’s goals are an essential part of the diagnostic evaluation. The American Urological Association recommends that if a patient’s symptoms are not bothersome if they do not want treatment, then no further work-up is recommended. This is because the condition is unlikely to significant affect their future health.

Information on Prostate Enlargement

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

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 (PVR), measures how much urine is left in the bladder after urination. The PVR can be measured through a bladder scanner which uses ultrasonography. A high PVR may indicate treatment failure or the need for surgical intervention. 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 antigen (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, lifestyle changes 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. Lifestyle changes include avoiding or reducing consumption of alcohol and caffeinated beverages. Such drinks are classified as diuretics, which promote urine production. Other changes involve avoiding fluids before bed and avoiding medications, such as certain antihistamines or decongestants that can worsen urinary retention. If the symptoms are severe and the urinary or reproductive tract is affected, however, then BPH needs to be treated.

Most men seek treatment for symptomatic relief and this is the goal of treatment. 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. Some patients may experience spontaneous improvement.

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 which improve urinary flow. These are usually first-line pharmacological therapy. 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 and prevent further BPH progression. 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. In certain cases, a combination of an alpha-blocker and 5-alpha-reductase inhibitors may be used. Phosphodiesterase inhibitors can also improve symptoms of BPH as well as erectile dysfunction. Examples of such drugs are Tadalafil.

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 efficacy 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 favorable result, as was seen in the case of saw palmetto. Further, the American Urological Association does not recommend the use of herbal remedies.

Surgery is usually reserved as second-line treatment for patients who did not respond to medical therapies. Surgical management of BPH includes transurethral resection of the prostate (TURP), transurethral incision of the prostate (TUIP), open surgery (prostatectomy), and laser surgery. These surgeries destroy or remove tissue around the prostate or urethra. TURP is the most common surgical option; the surgeon uses an instrument called a “resectoscope” to remove enlarged prostate tissue through the urethra. Complications include sexual dysfunction and urinary issues. 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. Rather, the incisions widen the urethra. 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 interstitial laser coagulation. Ablation procedures may be preferred for men with bleeding disorders because there is less blood loss. Removal of obstructing prostate tissue by these methods can allow better urinary flow. Mechanical approaches such as balloon dilation and urethral stent placement dilate the obstructed area of the urethra. Balloon dilation involves placing a catheter with a balloon at its tip through the urethra; the balloon is inflated in the area of obstruction. Urethral stents 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 inflammation has been implicated in BPH. Studies have shown that tissue specimens from enlarged prostates have proinflammatory cells and cytokines. This may explain why obesity, which causes increased inflammatory cytokines, is associated with BPH. One cytokine 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.

Further, inflammatory markers, such as C-reactive proteins, correlate with increased lower urinary tract symptoms. Prostate epithelial cells also secrete hypoxia-inducible factor (HIF)-a alpha (coding protein) in response to inflammation. This is proposed to cause testosterone-induced hyperplasia. Investigators found that Heat shock protein (HSP) 27, which mediates immune responses, increases with inflammation in prostate tissue.

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.

For Further Information:

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Citation Types

Type

Format

MLA 9th

Muraca, Joseph. "Prostate Enlargement." Magill’s Medical Guide, 9th Edition, edited by Anubhav Agarwal,, Salem Press, 2022. Salem Online, online.salempress.com/articleDetails.do?articleName=MMG2022_1112.

APA 7th

Muraca, J. (2022). Prostate enlargement. In A. Agarwal, (Ed.), Magill’s Medical Guide, 9th Edition. Salem Press. online.salempress.com.

CMOS 17th

Muraca, Joseph. "Prostate Enlargement." Edited by Anubhav Agarwal,. Magill’s Medical Guide, 9th Edition. Hackensack: Salem Press, 2022. Accessed September 16, 2025. online.salempress.com.

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