Minimally invasive blocking of the blood supply to a man’s enlarged prostate improves symptoms as well as the most common current “gold standard” treatment, but carries none of the associated surgical risks, according to a study by researchers in Portugal presented at a conference in the US this week.
The early and medium term results of this study into prostatic artery embolization or PAE are significant because they show PAE achieves comparable clinical results to that of the common surgical procedure “TURP”, short for transurethral resection of the prostate, without the surgical risks, such as sexual dysfunction, urinary incontinence, retrograde ejaculation and blood loss, said study author Dr João Martins Pisco, chief radiologist at Hospital Pulido Valente and director of interventional radiology at St Louis Hospital, both in Lisbon.
However, certain urodynamic results (such as flow rate of the urinary stream), were not as good with PAE as with TURP.
The findings were presented at the Society of Interventional Radiology’s 36th Annual Scientific Meeting in Chicago this week.
Enlarged prostate, known as benign prostatic hyperplasia (BPH), is so common in men, it is often said that every man, if he lives long enough, will have it.
BPH is not cancer, it is a condition where, as he gets older, a man’s prostate gets bigger. Since the prostate surrounds the urethra, the tube that delivers urine from the bladder to the penis, there comes a point when its enlargement starts to squeeze the tube and impede flow. This causes symptoms like weaker urine flow, a need to pass urine more frequently or more urgently, and incomplete bladder emptying.
Pisco, who is also a professor at the Faculty of Medical Sciences, New University of Lisbon, said “such symptoms can have significant negative impact in quality of life, leading many men to seek treatment,” and we need new and inventive technologies like PAE to achieve better results with fewer side effects.
Currently the most common operation to remove an enlarged prostate is TURP. The procedure, which is usually done under general anasthetic, takes up to 90 minutes and normally involves the surgeon inserting an endoscope up the urethra through the penis and cutting away the middle of the enlarged prostate piece by piece.
Some men undergo complete removal of the prostate, a prostatectomy, via abdominal incision.
Such procedures normally require that the patient spend several days in hospital recovering.
Because of the proximity of the prostate to the urethra, the surgical procedures are not without risk. Pisco said men frequently experience a range of complications, including severe pain, blood loss, sexual dysfunction, impotence, retrograde ejaculation (where semen gets into the bladder), urinary incontinence, urethral stricture and infections.
An advantage with PAE is that there is no size limitation as with TURP, which can only be performed on prostates smaller than 60 cc.
“The best results are obtained on patients with prostates larger than 60 cubic centimeters and with very severe symptoms,” said Pisco.
“Pelvic arterial embolization may be the only feasible and effective treatment for benign prostatic hyperplasia in those men who cannot have TURP due to the size of their prostate (80 cc or more) or because it is inadvisable for them to undergo general anaesthesia,” he added.
Other treatments for enlarged prostate, apart from PAE, TURP, and prostatectomy, include watchful waiting, medication that relaxes the muscles near the prostate to ease symptoms, medication that shrinks the prostate, and other minimally invasive methods such as transurethral needle ablation and laser surgery.
Pisco said these other options are often less effective in improving symptoms, or don’t last long, and may involve continued catheterization and reoperation.
“Additional research is needed to explain why some patients improve better than others,” he added.
For their PAE study, Pisco and colleagues recruited 84 men aged from 52 to 85 with symptomatic BPH. They underwent PAE after unsuccessfully trying other medical treatments for a minimum of six months.
Pisco said they followed the men for an average of nine months after PAE. The results showed PAE was successful in 98.5% of cases, with 77 men showing “excellent improvement”, 6 men showing “slight improvement” (but not requiring medication), and one man showing “no improvement” (his PAE was incomplete).
In the men showing “slight improvement” it had not been possible to embolize both of the arteries that feed blood to the prostate because of advanced atherosclerosis (considerable plaque deposits on the inside walls of the arteries), said Pisco.
The researchers used pelvic magnetic resonance and computed tomography to scan the arteries first to see if they were suitable for PAE.
Pisco said two hours after their PAE, most men were already passing urine less frequently.
The PAE procedure itself is carried out by an interventional radiologist like Pisco, a doctor who is trained to carry out these types of embolizations and other minimally invasive procedures.
The radiologist makes a tiny cut into the patient’s femoral artery, and using real time imaging, guides a microcatheter through the artery and releases tiny particles, each about the size of a grain of sand, into the arteries that supply blood to the benign growth in the prostate. These block the blood flow, causing the prostate to shrink.
Most men only experience either no pain or a slight pain, and leave hospital four to eight hours after the operation, said Pisco.
“There is no sexual dysfunction following prostatic artery embolization, and a quarter of our patients report that sexual function improved after the procedure,” he added.
“Prostatic Artery Embolization to Treat Benign Prostatic Hyperplasia — Short- and Medium-Term Outcomes.”
J.M. Pisco, L. Campos Pinheiro, T. Bilhim, H. Rio Tinto, V.V. Santos, J.E. O’Neill
Presented as Abstract 5 at Society of Interventional Radiology‘s 36th Annual Scientific Meeting, in Chicago, Illinois, 26-31 March 2001.
Source: Society of Interventional Radiology (29 Mar 2011).
Written by: Catharine Paddock, PhD