Prostatic artery embolisation (PAE)

Benign enlargement of the prostate (BPH) is the most common type of benign tumour in men and primarily occurs in later life. More than half of men over 60 have this type of organ enlargement, with the number increasing to 70% over 70. However only just under a third of them will develop symptoms that impact on their quality of life.

Symptomatic BPH is initially treated with medications, which allows mild symptoms to be controlled effectively. If this treatment is not sufficient, patients are generally advised to have part of their prostate surgically removed. PAE provides a new, minimally invasive alternative to surgery for such cases.

PAE interrupts the flow of blood from the arteries supplying the prostate. Tiny plastic particles are introduced into the arteries and sealed inside the prostate so that larger parts are no longer supplied and shrinkage occurs.

The aim of PAE is to reduce the volume of the benignly enlarged prostate so that the characteristic symptoms such as increased and prolonged urge to urinate can be reduced or eliminated. In three quarters of patients, this treatment leads to a rapid and permanent improvement in their symptoms.

PAE is potentially suitable for all men who have symptoms associated with benign enlargement of the prostate – be they straightforward symptoms such as increased need to urinate, a poor urinary stream and long terminal dribbling after passing urine, or whether they are serious consequences of the condition in which the patient is no longer able to fully empty the bladder, or if the patient is incontinent, if there is kidney damage due to the chronic back-flow of urine or if there are recurrent urinary tract infections.

PAE may also be an alternative for patients who do not want the typical consequences of conventional trans-urethral resection (TURP) or retrograde (backwards-facing) resection. It can also most importantly be a less drastic alternative for very large glands of over 80 ml in volume which would normally be treated with open surgery.

Beforehand

First we ensure that the symptoms are actually being caused by BPH. The typical symptoms are surveyed with a questionnaire and evaluated. Flow dynamics while urinating are investigated and the prostate enlargement is documented with an ultrasound scan or MRI scan.

We also need to rule out a malignant prostate cancer, since this would require a very different treatment. To do this, we determine the concentration of prostate-specific antigen (PSA) in the blood. If the PSA level is raised – which can sometimes occur with (benign) BPH – we investigate in more detail with an MRI scan and possibly a biopsy.

To plan a PAE procedure that is as safe and as non-invasive as possible, the pelvic vessels are also visualised accurately and in particular the vessels supplying and draining from the prostate gland, using MRI or CT scans.

This careful work-up process also provides us with information on how badly calcified the blood vessels are. In cases of severe calcification, PAE cannot be carried out.

During

Patients are admitted for around three to five days for the treatment.

An approximately 2 mm hole is made in the groin, via which a thin catheter is guided into the blood vessel and up to the organs of the pelvis. From there, an even finer catheter (approx. 1 mm in diameter) is passed into the branches of the vessels that supply the prostate with blood. The correct position is checked under X-ray control. Tiny plastic particles are then passed into the blood vessels supplying the enlarged prostate, blocking off the blood supply.

Before, during and after the procedure the patient is given medication to ensure that the experience is as pain-free as possible. Anaesthesia and its attendant risks can be avoided with PAE.

After

After treatment, we document the residual symptoms using a standardised questionnaire, just like before the PAE, and compare it with the original values.

Around half of patients find they have had a significant improvement in their symptoms even by the time they are discharged. After 4-6 weeks, the success of the treatment can be evaluated more definitively.

For the scientific analysis of the results of this new treatment method, we carry out a further MRI scan of the prostate to determine any changes in size.

Side effects from this treatment are rare and in most cases are easily treated. They include slight pain or a burning sensation in the urethra or anus during the embolisation, despite the pain medication (experienced in around 9% of patients), urinary tract infections that are effectively treated with antibiotics (7% to 8%), or acute urinary retention (in 2% to 3%) which can be overcome by temporarily inserting a urinary catheter into the bladder.

Other, less common side effects include blood in the urine or small blood deposits in the stool for a few days after the PAE.

Added to this are the general risks associated with any catheter-based investigation, such as haematoma (bleeding) at the puncture site in the groin or an intolerance of the contrast medium. Thanks to thorough preparation for the treatment and careful follow-up, however, these complications are very much an exception.

Unlike surgical treatment options, so far no short or long-term negative effects have been described on sexual potency or continence. Since many patients are able to discontinue their medications, there is often a reported increase in the ability to get an erection.

Figure 1: Front view of the prostate gland of a 55-year-old patient with changes typical of benign prostate enlargement. The transitional zone around the urethra is significantly enlarged (arrows).
Due to recurrent urinary retention, the patient has a bladder catheter in place (star).

Figure 2 a: Angiography of the patient. A guide catheter was inserted into the inner left pelvic artery (star), and through this a fine micro-catheter was guided into the arteries supplying the prostate gland (thin arrow).
The blood vessels within the prostate are indicated by large arrows.

Figure 2 b: Following embolisation, the small vessels within the prostate are no longer visible (large arrow).
However, the main vessels continue to be supplied with blood (small arrows), in order to ensure a blood supply to the other organs.
The vessels supplying the right-hand side of the prostate were then also embolised.

Contact


Minimally Invasive Tumour Therapy (MITT)
Charité Campus Virchow-Klinikum (CVK)
Department of Radiology
Augustenburger Platz 1
13353 Berlin

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