Benign prostatic hyperplasia

Benign prostatic hyperplasia: description

Benign prostatic hyperplasia (BPH) describes a benign prostate enlargement. “Benign” means that there is an increase in the number of cells in the prostate, but this is not as aggressive and run unchecked as in malignant growth (cancer). Correspondingly, the proliferating tissue does not grow into other structures in benign prostatic hyperplasia and does not spread. So there are no daughter tumors (metastases) as in prostate cancer.

Benign prostatic hyperplasia is thus neither a form of cancer nor a precursor thereof. Nevertheless, the increase in volume of the organ causes increasing discomfort for those affected.

Location and anatomy of the prostate

The prostate (prostate gland) is similar in shape and size to a chestnut. It is located just below the bladder and in front of the rectum. In the normal state, it weighs between 20 and 25 grams, with pronounced benign prostatic hyperplasia, however, up to 150 grams.

The top of the urethra passes through the prostate. In addition, in the prostate the vas deferens (transports the sperm from the testicles) and the excretory duct of the seminal vesicle (produces secretion for the ejaculate) unite to form the so-called Spritzkanälchen. This also flows within the prostate into the urethra. The vas deferens, seminal vesicles and spray canals are paired.

The prostate can be divided from the inside out into three zones:

The innermost zone (peri-urethral mantle zone or transition zone) directly surrounds the urethra. In it are small secretory glands. The next layer is the “inner zone”. It accounts for about a quarter of the total mass of the prostate. The two spray channels run in it. The outermost layer (outer zone or peripheral zone) also contains secretory glands. They account for almost three quarters of the prostate weight. On the outside, the prostate is surrounded by a tough connective tissue layer (capsule).

Function of the prostate

The prostate (prostate gland) consists of many smaller glands that create a secretion that protects the sperm and stimulates movement. It accounts for 30 percent of the ejaculate and is delivered to the urethra. In addition, the so-called prostate-specific antigen (PSA) is formed in the prostate – an enzyme that makes the sperm fluid.

Between the glands of the prostate lie layers of connective tissue and smooth muscle. Muscular cells allow the prostate to contract rhythmically during orgasm, thus expelling the ejaculate.

What happens in benign prostatic hyperplasia?

The term “hyperplasia” in medicine refers to the excessive increase in the cell count of a tissue. In the case of prostate hyperplasia, this affects above all the cells of the connective and muscle tissue located between the glands, but also the gland cells themselves. The increase in the number of cells is due to the current state of research, that the natural cell death (apoptosis) is slowed down (not through an increased cell proliferation).

The increase in the number of cells in benign prostatic hyperplasia is shown only in the peri-urethral mantle zone. The outer zone of the prostate gets more and more strained by the growing transition zone, until it appears only as a thin layer. Since there are many glands in the outer zone, it can also be explained that in benign prostate hyperplasia, the secretion performance of the prostate gland decreases somewhat, although there are more cells overall.

In contrast to benign prostate enlargement, prostate cancer has an uncontrolled growth of the outer zone, while the transition zone is unaffected.

BPO, LUTS, BPS, prostate adenoma – terms related to prostate hyperplasia

The term benign prostatic hyperplasia (BPH) refers, as described above, merely to the size or volume increase of the prostate, but not to associated symptoms. Therefore, some terms appear confusing, which often appear in connection with the benign prostate enlargement and should be briefly explained here.

Benign prostate obstruction (BPO): Benign prostatic hyperplasia can increase so-called bladder outlet resistance. This term refers to the resistance that the bladder needs to overcome in order to move the urine collected from it through the urethra. Some resistance is normal and necessary to prevent constant, uncontrolled urination. In the case of prostate hyperplasia, however, the resistance may be abnormally elevated because the enlarged prostate gland narrows the urethra. The possible consequences are problems with urination. In this case, doctors talk about benign prostate obstruction, BPO for short.

Lower urinary tract symptoms (LUTS): Many symptoms of benign prostatic hyperplasia (such as urinary frequency or decreased urinary stream) affect the lower urinary tract, the bladder and urethra. Therefore, these symptoms are summarized under the term “lower urinary tract symptoms”. In the English language one says accordingly “Lower Urinary Tract Symptoms”, the abbreviation for it is LUTS.

Benign Prostate Syndrome (BPS): If there is benign prostatic hyperplasia and there is also obstruction (BPO) and lower urinary tract symptoms (LUTS), this complex is referred to as “benign prostate syndrome” (BPS). Ultimately, a BPH requiring treatment is always a BPS, as the symptoms are crucial for therapy rather than the mere enlargement of the prostate gland.

prostate adenoma: The term prostate adenoma is sometimes used synonymously for benign prostatic hyperplasia, although this is actually incorrect. Because an adenoma describes in medicine an excessive benign growth of cells of the mucous or glandular tissue. In benign prostatic hyperplasia, not only the gland cells are affected by the increase in the number of cells, but also connective tissue and muscle cells. Nevertheless, the term prostate adenoma is often used as a synonym for benign prostatic hyperplasia.

Benign prostatic hyperplasia: frequency

Benign prostatic hyperplasia is the most common urological disease in men. It is also a typical phenomenon of old age. While young men usually have no complaints with their prostate gland, especially men over the age of 50 imagine the urologist, because they have difficulty urinating. The pathological enlargement of the prostate in the medical sense has occasionally been diagnosed earlier (about the age of 35), but then usually has no disease value because symptoms initially fail.

The presence of benign prostatic hyperplasia is therefore relatively common at a certain age, but only a part of those affected feel the typical symptoms. For example, every second man between the ages of 50 and 60 has an enlarged prostate. However, clinically relevant symptoms show only 10 to 20 percent of men in this age group. For the 60- to 69-year-olds, by contrast, around 70 percent have prostate enlargement and 25 to 35 percent noticeable symptoms.

Benign prostatic hyperplasia: symptoms

Which symptoms and complications a benign prostate enlargement can cause can be read in the article Benign Prostatic Hyperplasia – Symptoms.

Benign prostatic hyperplasia: causes and risk factors

The causes of benign prostatic hyperplasia are ultimately not sufficiently understood. It is clear that certain factors play a role. The exact connections and processes that lead to a benign prostate enlargement, but are still the subject of research.

hormones

It is certain that the male hormone balance plays an essential role in the development of benign prostatic hyperplasia. Thus, the presence of male sex hormones (androgens), especially testosterone, is necessary for BPH to develop at all. Accordingly, castrated men can not get benign prostatic hyperplasia: because they no longer have testicles (main testosterone sites), they have very low levels of the hormone.

Testosterone appears to induce growth of the transition zone of the prostate gland as males age. The exact processes behind it have not yet been finally clarified. The testosterone does not act directly on the prostate, but is previously in the cells within the prostate gland in a more effective form – the so-called dihydrotestosterone (DHT) – converted. The enzyme that facilitates this transformation is called 5α-reductase. Although dihydrotestosterone is not only produced in the prostate and its effect is not limited to this organ, it is essential for the development of benign prostatic hyperplasia.

It is believed that not only testosterone (or dihydrotestosterone), but also female sex hormones (estrogens) have a certain importance in the development of benign prostatic hyperplasia. It should be noted that men also have estrogens, albeit in smaller quantities than women. Conversely, women also have a low concentration of testosterone and other androgens in their blood. With age, the testosterone content in men decreases, while the estrogen level remains approximately the same or even increases. This leads to a (relative) increase in estrogens, which obviously promotes BPH.

Because estrogens are sometimes also produced in fat cells, severe obesity is a risk factor for benign prostatic hyperplasia.

Changes in the extracellular matrix

In addition to hormones, there is another aspect that is suspected to contribute to the development of a benign prostate enlargement: an altered effect of the so-called extracellular matrix (ECM) of the prostate on the cells of the organ. The extracellular matrix is ​​generally referred to as the area between the cells of a tissue. If certain changes take place here, growth factors can be increasingly linked to ECM and cause cell proliferation. Such growth factors can also be increasingly produced by the body and stimulate cell division in the prostate tissue or prevent the natural death of the cells. This can promote benign prostatic hyperplasia.

Genetic factors

Genetic factors play a minor role in benign prostatic hyperplasia. The likelihood of a genetic component as a cause of BPH is higher when prostate enlargement becomes clinically relevant at a relatively young age. If, for example, a benign prostatic hyperplasia has to be operated on before the age of 60, then it has familial, ie genetic, causes in 50 percent. In men over the age of 60, on the other hand, only about 9 percent of cases with BPH requiring treatment are genetically determined.

Benign prostatic hyperplasia: examination and diagnosis

The different examination methods serve on the one hand to confirm the diagnosis of a benign prostate enlargement. On the other hand, it is important to exclude other diseases that may cause similar symptoms (such as frequent urination or a broken urinary stream) such as benign prostatic hyperplasia.

In general, individual examination results usually can not sufficiently demonstrate benign prostatic hyperplasia. Only the synopsis of several findings provides the diagnosis.

Survey of the medical history (medical history)

In a detailed conversation with the patient, the doctor asks for the exact symptoms. He also inquires about any pre-existing conditions and previous interventions that might be the cause of the complaints.

For example, a stricture of the urethra may not only be due to prostatic hyperplasia, but may also be due to a previous inflammation or catheter. Diseases such as diabetes mellitus, Parkinson’s disease, or heart failure (heart failure) may also partially resemble the symptoms of benign prostatic hyperplasia with their symptoms. In some cases, certain medications (anticholinergics, antidepressants, neuroleptics) are the cause of the symptoms.

Estimation of the severity of the symptoms

To objectively assess the extent of the symptoms, the doctor uses the International Prostate Symptoms Score (IPSS). The patient is asked about a total of 7 typical symptoms of BPH (such as residual urgency, nocturnal urgency, etc.): On a scale of 0 to 5, he should indicate how much he feels the individual complaints. The more pronounced a symptom, the higher the number of points awarded. The total result can therefore be a maximum of 35.

It should be noted that the IPSS is not a method to diagnose benign prostatic hyperplasia. It merely serves to determine the intensity of certain complaints that can occur in benign prostate enlargement as well as in other diseases.

The Digital-Rectal Examination (DRU)

The most important physical examination for the clarification of prostate hyperplasia is the so-called digital-rectal examination, DRU for short. The doctor introduces his finger (Latin digitus) into the rectum of the patient and palpates the prostate, which is located directly in front of the rectum.

If benign prostatic hyperplasia is present, then this can be determined with the help of the DRU if the prostate has already increased sufficiently. The prostate usually feels plump-elastic and smooth. In contrast, it appears in a prostate enlargement by cancer usually rock hard and uneven.

The DRU is only for rough orientation; Their result always depends on the experience of the doctor. In no case can the diagnosis of a benign prostatic hyperplasia be made solely by the findings of a DRU.

Further physical examinations

In addition to the DRU, the physical examination to determine a benign prostatic hyperplasia and certain reflexes, any nerve failures and the function of the sphincter are checked.

Urine and blood tests

Laboratory diagnostics can also provide important information for the clarification of benign prostatic hyperplasia. On the one hand, the urine status is checked: The urine is examined for possible infections.

On the other hand, certain laboratory parameters are collected. These include the prostate-specific antigen (PSA), which can often be elevated in prostate cancer and thus should be used to rule out malignant prostate enlargement.

In addition, the blood concentrations of urinary substances (retention parameters) are measured in order to detect kidney damage and uremia in good time.

Ultrasound (sonography)

Ultrasound examination is an important method to clarify relevant questions in a BPH. For example, with their help, statements can be made about the residual urine quantity and the prostate size. In addition, the thickness of the detrusor can be determined by means of ultrasound and possible complications such as bladder stones or pseudodiverticula can be detected.

As a rule, the ultrasound examination is carried out transrectally, ie via an examination device (transrectal ultrasound, TRUS) introduced into the rectum (rectum). The amount of residual urine can also be well sounded through the abdomen (transabdominal ultrasound).

Urine flow measurement (uroflowmetry)

Urinary flowmetry is used to determine the urinary stream. The patient urinates in a special funnel, which can measure via sensors, how much urine flows through each time unit. For this study to be truly meaningful, a minimum of 150 milliliters should be urinated.

A normal urine flow is approximately 20 milliliters per second (ml / s). Everything below 10 ml / s, on the other hand, is highly suspicious of narrowing of the urethra, for example due to benign prostatic hyperplasia. Uroflowmetry is relatively easy to perform and inexpensive.

Other apparatus examination procedures

There are still other apparatus methods that are not necessarily used by default, but only in certain cases.

The Urethrocystometry (urodynamics) For example, allows statements about the pressure that prevails during micturition in the bladder. This helps to distinguish an obstruction by prostatic hyperplasia from a pure weakness of the bladder muscle (detrusor weakness).

At a Excretory urogram (urography) The patient is administered contrast agent via a vein and then an X-ray of the lower abdomen is made. The renal excretion and urinary tract can be assessed.

In contrast, at one urethrogram the contrast agent is injected through the urethra into the urinary bladder, allowing an assessment of the urethra.

Occasionally, benign prostatic hyperplasia is also diagnosed Bladder reflexion (cystoscopy) for use.

In order to be able to reliably differentiate a benign prostate enlargement from a malignant one, a small amount must be spread over the rectum tissue sample are removed from the prostate gland and then examined closely.

Benign prostatic hyperplasia: treatment

Benign prostatic hyperplasia is not necessarily in need of therapy. As long as she does not complain, it often suffices to wait and see the progression of the disease regularly. However, with IPSS above 7 or general patient distress, treatment with benign prostate enlargement usually begins. “Treatment” initially means mostly the use of drugs. Surgical procedures are first considered for increasing discomfort or complications from prostate enlargement.

Drugs for benign prostatic hyperplasia

In benign prostate enlargement stage I and mild forms of BPH stage II after alkene (described in the article ), a drug treatment is usually sufficient. There are various drug groups available, some of which can be combined with each other.

Plant preparations (phytopharmaceuticals): There are several herbal medicines that can be used to treat benign prostatic hyperplasia with mild discomfort. These include, for example, preparations based on saw palmetto, rye, nettle root, African plum and pumpkin seed. The mode of action of the various plant substances varies: some inhibit, for example, the enzyme 5α-reductase or certain growth factors, others promote natural cell death. Many phytopharmaceuticals also contain so-called beta-sitosterone – substances that inhibit male sex hormones, ie have an antiandrogenic effect.

Herbal medicines are available over the counter and are usually very low in risk. They are therefore preferred by many patients to other medicines. However, the therapeutic efficacy of pumpkin seed and Co. has not yet been sufficiently substantiated by studies; especially the long-term effect is considered questionable. In the US, phytopharmaceuticals for the treatment of benign prostatic hyperplasia have been banned for many years because of fears that they will discourage patients from undergoing BPH.

α-blockers: The α-blockers (more precisely: α1-adrenoceptor antagonists) ensure that the muscles on the prostate and urethra relax, which improves the urine flow. This is possible because α-blockers prevent the attachment of certain messenger substances to receptors of the musculature, which would otherwise trigger a contraction of the muscle cells. However, α-blockers have hardly any influence on the size of the prostate, which is why the mechanical flow obstruction from the bladder is only slightly affected.

Originally, α-blockers were not developed for the treatment of benign prostatic hyperplasia, but as antihypertensive drugs. This explains why they sometimes have side effects on the cardiovascular system. In addition, dizziness, headache, fatigue and swelling of the nasal mucosa sometimes occur. Classic drugs from the group of α-blockers are, for example, alfuzosin, doxazosin, tamsulosin and terazosin.

5-α-reductase inhibitors: The 5-α-reductase inhibitors block the function of the enzyme 5-α-reductase and thus the conversion of testosterone to dihydrotestosterone. These are the main growth-stimulating factor inhibited in a benign prostatic hyperplasia – the prostate does not increase further; it may even shrink again. However, it may take up to a year for the patient to notice any significant improvement in symptoms.

The two active substances with a blocking effect on 5-α-reductase are called finasteride and dutasteride. Their typical side effects include loss of libido, impotence and a decrease in male body hair.

Phosphodiesterase inhibitors (PDE inhibitors): A blockade of the enzyme phosphodiesterase has a similar effect in benign porstatic hyperplasia as the inhibition of α-reductase: The muscles of the urinary bladder and urethra relax, which facilitates the voiding. In addition, PDE inhibitors such as tadalafil have a positive effect on erectile dysfunction (impotence), which can occur as part of a prostate enlargement.

anticholinergics: These active ingredients have a damping effect on the bladder muscle (detrusor). They are used to treat the irritative symptoms of benign prostatic hyperplasia, such as imperative urgency. In case of severe obstructive symptoms, however, the use of anticholinergics must be carefully weighed, as a weak detrusor muscle may even be counterproductive.

Surgical procedures for benign prostatic hyperplasia

From a certain severity of symptoms, the mere use of drugs is no longer sufficient. Then, surgery is the drug of choice for treating benign prostate enlargement. Surgery is not the same operation: There are a variety of surgical procedures that can be used in BPH. The most important are described below. Which method is ultimately used always depends on the individual case.

TURP: The standard procedure for the surgical treatment of benign prostatic hyperplasia is “transurethral resection of the prostate” (TURP). Similar to a bladder mirror, a small tube is inserted into the urethra. It has a tiny camera and a metal loop over which electrical current flows. With the aid of the sling, the enlarged tissue of the prostate is now removed layer by layer. Thanks to recent developments in the area of ​​TURP, side effects are rare.

TUIP: A modification of the TURP is the “transurethral incision of the prostate” (TUIP). The technique is the same, but here no prostate tissue is removed, but only cut, at the transition between bladder neck and prostate. This gives the urethra more space. The TUIP is used in benign prostatic hyperplasia, especially if the prostate gland is not too big.

TUMT: “Transurethral microwave therapy” (TUMT) also takes place via the urethra. Here microwaves heat the prostate tissue to 70 degrees Celsius and destroy it. As a result, the organ shrinks. To prevent damage to the urethra, it is cooled during the TUMT by the flushing of liquid.

Laser method: Another way to treat benign prostatic hyperplasia is by using laser techniques (ILC, HoLEP). The prostate tissue is destroyed by laser beams or cut out and removed. Above all, the HoLEP procedure is considered equal to the TURP. However, it is hard to learn and therefore requires great experience.

Open operation: If the prostate is already very large or has certain complications, it may be useful to openly treat benign prostatic hyperplasia. One speaks then also of a Prostataenukleation. The surgeon opens the bladder and removes the prostate through it.

Benign prostatic hyperplasia: disease course and prognosis

Unless treated, benign prostatic hyperplasia usually progresses slowly. However, with medication, the process can often be stopped and in some cases even reduce the size of the prostate gland.

If the medication fails to work properly or the prostate hyperplasia is already too severe at the time of diagnosis, surgery usually helps.

Obesity and smoking are among the biggest risk factors for benign prostate enlargement. On the other hand, regular exercise and sport have a positive effect. A healthy lifestyle is the best way to be benign prostatic hyperplasia prevent.