Articles tagged with: Transperineal biopsy

08
September
2015

Prostate biopsy infection - antibiotic resistance

Prostate biopsy infection - antibiotic resistance

Infections associated with prostate biopsy have increased over time, and there is growing evidence of infections that are resistant to the antibiotics used to prevent infection.

Resistant infections after trans-rectal prostate biopsy (TRUS)

About 1-2% of patients who have a TRUS biopsy of the prostate will develop a febrile infection, which can be serious. Antibiotics (usually ciprofloxacin) are used before and after biopsy to keep this infection rate at 1-2%. However, there is increasing evidence that many of us carry bacteria in our gut (and rectum, where the needle is passed through to reach the prostate) that are resistant to ciprofloxacin.

A recent study from the Journal of Urology (Liss et al.) looked at 2673 men from 6 different medical centres undergoing biopsy and discovered cirpofloxacin-resistant bacteria in the rectum in 20.5% of men.

We know that some men are at increased risk of carrying such resistant bacteria (known as ESBL), and these include men who have been treated with ciprofloxacin in the prior six months, and those that have travelled to SE Asia or the Indian subcontinent in the recent past. The bacteria are harmless in the gut, but become dangerous if seeded into the prostate by biopsy.

How can the risk of infection be reduced?

One of the ways to reduce the risk of infection is to consider a transperineal biopsy instead of a transrectal biopsy. In transperineal biopsy, the needles for biopsy are not passed through the rectum, but instead through the skin of the perineum, and the infection risk is greatly reduced. A study from Jeremy Grummet in Melbourne demonstrated a reduction in serious infection, with a greater than 10x reduction in risk compared to transrectal biopsy.

You can read more about this study by following this link to an article by Jeremy Grummet.

Follow this link to read more about transperineal biopsy.



Categories: Updates, Prostate Cancer

19
February
2014

A Safer Way to Biopsy the Prostate

A Safer Way to Biopsy the Prostate

Jeremy Grummet is a Urological Surgeon with particular expertise in urological cancer. He has been instrumental in the introduction of transperineal prostate biopsy as an alternative to transrectal biopsy, to reduce infection rates after biopsy. Jeremy is conducting multiple clinical research projects on prostate biopsy and heads the Victorian Transperineal Biopsy Collaboration (VTBC) research group. In this article, Jeremy discusses the techniques and advantages of transperineal biopsy.


What’s wrong with the current standard method of prostate biopsy?

A biopsy is where a sample of tissue is taken for examination under a microscope, usually to determine if cancer is present. As you can see from the diagram below, the easiest way to access the prostate is via the rectum. That’s why we perform a rectal examination - so we can feel the back of the prostate for any suspicious lumps. Most prostate cancers are located towards the back of the prostate (peripheral zone), so a transrectal ultrasound-guided (TRUS) biopsy is a convenient way of sampling this area. Typically, at least 12 cores of tissue are taken during a TRUS biopsy.

TRUS biopsy

The other advantage of the TRUS biopsy is that it can be performed in just a few minutes by giving the patient intravenous sedation or using a local anaesthetic nerve block.

However, passing the needle of the biopsy gun through the wall of the rectum multiple times is problematic. As you’d expect from an organ that stores faeces, the rectum has a high concentration of bacteria. These bacteria don’t cause any problems as long as they stay in the rectum. However, passing the biopsy needle through the wall of the rectum allows these bacteria to access the prostate and its rich blood supply. This in turn can lead to a serious infection in the blood called septicaemia (sepsis). Septicaemia makes patients feel very unwell, requires hospitalization for intravenous antibiotic therapy, and can even be life-threatening.

This risk of sepsis in TRUS biopsy is well-recognised. It is therefore standard to use an antibiotic to help prevent such an infection. Unfortunately, the antibiotic doesn’t always work, so there is still a risk of sepsis, which has been measured at about 1-2%.

Today, there is the additional and growing problem of bacteria developing antibiotic resistance. This has been reported worldwide and was the subject of a major US Government report last year.

Our own research group, the Victorian Transperineal Biopsy Collaboration (VTBC), reviewed the scientific literature, finding that developing resistance is a particular problem for bacteria that live in the rectum, so that the antibiotics we would normally use, such as ciprofloxacin, can sometimes be rendered ineffective. This coincides with reports of increasing rates of TRUS biopsy sepsis even as high as 5%.

Our research has also found that, as a result of the above, some Australian and New Zealand urology practices have resorted to using big-gun broad-spectrum antibiotics on a regular basis to prevent TRUS biopsy sepsis. Whilst this may reduce sepsis for the individual patient, from a public health perspective, it is a step backwards, as widespread use of such antibiotics will lead to even more resistance. Unfortunately, we are already seeing this happening, with hospitals in Australia finding CRE (Carbapenem-Resistant Enterococci) in their wards.


What is transperineal biopsy, and why is it safer?

Fortunately, there is another approach to prostate biopsy which avoids perforation of the rectum altogether. Instead, the biopsy needle can be passed via the skin of the perineum. In men, the perineum is the part of the body between the scrotum and the anus.

TRUS biopsy

As shown in the diagram, the ultrasound probe is still passed into the rectum to provide an image of the prostate. But instead of the biopsy needle passing alongside the probe, it is passed through a grid, which itself is fixed against the probe outside the body. Prior to insertion of the ultrasound probe, the perineal skin is easily prepared in a sterile fashion, just as any other incision site is prepared before surgery to prevent wound infection. (Although worthwhile attempts have been made to sterilize the rectum, this has not been possible.)

Our group studied the experience of transperineal (TP) biopsy around the world and found that in over 6,600 patients, there were only 5 patients re-admitted to hospital for sepsis - a rate of just 0.076%, or less than 1 in a thousand. Furthermore, in our own published experience of 245 TP biopsies our rate of re-admission for infection was zero. (We have now performed over 400 TP biopsies, still without a single episode of infection.)

Based on the published scientific evidence to date then, it appears that TP biopsy is a safer option than TRUS biopsy due to its near-zero sepsis risk. It also gives the advantage of avoiding regular use of heavy-duty antibiotics, thereby avoiding promotion of resistant bacteria, now labelled by the US Government Center for Disease Control as a Serious Threat to population health worldwide. As a result, we now use TP biopsy routinely for all prostate biopsies.


Are there any downsides to the transperineal approach?

Looking at the diagram above, you would expect TP biopsy to be painful, which is why it is typically performed under a general anaesthetic (although methods of using local anaesthetic only have been reported). We routinely perform TP biopsy under GA. As a result, men experience no pain during the procedure, and very little afterwards, so that paracetamol is only required occasionally. Although a general anaesthetic is required, it is of a short duration only (less than 30 minutes) and is very safe.

Practitioners of TP biopsy initially reported a higher risk of acute urinary retention (unable to pass urine) with this approach. However, with further experience, and by deliberately avoiding the area around the urethra, this rate dropped so that it is now similar to the risk seen in TRUS biopsy (around 2%). Although a catheter has been used by some doctors, as shown in the diagram above, it is unnecessary.

Due to anecdotal experience, some urologists have been concerned that TP biopsy may lead to erectile dysfunction by damaging the erectile nerves or to more difficult surgery if cancer is found and the prostate needs to be removed. However, evidence to date, albeit scant, does not support either of these concerns.


Is it as good as TRUS at cancer detection?

According to the scientific literature, TP biopsy is at least equivalent to TRUS biopsy in its ability to detect cancer. Some research has also found improved detection of cancers at the front of the prostate (anterior). This may be due to the typically easy access TP biopsy provides to all areas of the prostate, particularly anteriorly. Conversely, it can often be difficult to reach the anterior prostate via TRUS biopsy, especially in large glands.


What other advantage might TP biopsy provide?

In TP biopsy, the ultrasound probe is stabilized by equipment that is fixed to the operating table. The grid through which the biopsy needle is passed is, in turn, stabilized against the ultrasound probe. This set-up permits accurate and reproducible biopsy needle placement.

In the past, TP biopsies were taken in a systematic fashion only, evenly sampling various areas of the prostate. Whilst this is still performed routinely, in addition we are now often performing targeted biopsies of suspicious lesions if found on a prostate MRI. The stable arrangement of TP biopsy therefore permits accurate targeting of such lesions, with the potential to further improve the accuracy of cancer detection.


You can read more about Jeremy Grummet by clicking this link

There is more information on transperineal biopsy on the AUA site.

And you can follow @JGrummet on Twitter.


Categories: Updates, Prostate Cancer, Prostate Surgery

14
October
2013

Biopsy Techniques for Prostate Cancer

Biopsy Techniques for Prostate Cancer

This week’s Guest Post is by highly regarded expert in the early detection of prostate cancer, Dr. Stacy Loeb. Stacy takes questions on prostate biopsy, and discusses its use, potential problems, and some developments in the field.

Dr Stacy Loeb is an Assistant Professor of Urology and Population Health at New York University (NYU) and the Manhattan Veterans Affairs Medical Center, specializing in prostate cancer. Dr. Loeb has published over 170 peer-reviewed articles and 8 book chapters, primarily on prostate cancer. She is on the Editorial Board for the British Journal of Urology International and Reviews in Urology, and authored the chapter on “Early Detection, Diagnosis, and Staging of Prostate Cancer” for Campbell-Walsh Urology, the primary textbook for the field. Stacy also frequently gives international lectures and courses on prostate cancer for other urologists, and hosts the Men’s Health Show on Sirius XM 81 satellite radio.


Stacy, TRUS biopsy is the most common technique for the diagnosis of prostate cancer. Can you give us an idea of the potential complications and the rates at which they occur?

The most common complication of prostate biopsy is bleeding, which can be in the urine, stool or ejaculate. Fortunately in most cases it is mild and self-limiting. Less common but often more serious is the potential for infection after biopsy. Indeed, the frequency of serious infections requiring hospitalization after prostate biopsy has increased in recent years. Other potential complications of prostate biopsy include pain and urinary difficulties, which are usually transient.


Is it a painful procedure to have done, and what techniques are used to reduce pain?

Prostate biopsy can cause both discomfort and anxiety, although there are many ways to mitigate these problems. Optimising patient positioning and simple relaxation techniques (such as deep breathing, listening to music, or even medication) may be useful to reduce anxiety. For pain, many different anesthetic options are available. For transrectal biopsy, several studies have shown that lidocaine jelly can ease insertion of the ultrasound probe, which is among the more uncomfortable parts of the procedure. Periprostatic nerve block is also commonly employed to successfully reduce pain during outpatient transrectal prostate biopsies. Other forms of biopsy such as the transperineal approach are frequently performed under sedation/general anesthesia, also effective forms of pain control. Overall, there are very few high-quality studies comparing the different methods for pain reduction during prostate biopsy, so the choice may be governed by patient-specific and procedural factors.


Some men require more than one biopsy to diagnose prostate cancer. There has been concern that repeat biopsies can predispose men to erectile dysfunction; can you comment on this?

There is conflicting evidence on the link between repeat prostate biopsies and the risk of erectile dysfunction. A study from the Johns Hopkins active surveillance program suggested that greater biopsy number was associated with erectile dysfunction after adjusting age, prostate volume and PSA, but a similar study from UCSF failed to confirm these results. Possible mechanisms for a link between repeated biopsies and erectile dysfunction include psychological factors as well as potential inflammation in the area around that prostate that houses the nerves involved in erections. Although this issue remains unresolved at this time, each procedure has potential risks making careful patient selection of critical importance. Hopefully, ongoing improvements in markers and imaging will reduce the need for repeat biopsies in the future.


You mentioned infection rates above. Are we seeing a rise in infection following TRUS biopsy of the prostate, and if so, why?

In the United States Medicare population, our research group reported a recent increase in hospitalisations for infection after prostate biopsy. Similar results have been confirmed in other populations, including Canada and Europe. The most likely explanation for these findings is increasing antimicrobial resistance in the community. Traditionally, the majority of patients were given fluoroquinolones as prophylaxis for prostate biopsy, but fluoroquinolone resistance has been on the rise. As a result, recent studies have explored other options for prostate biopsy prophylaxis, One option is to use more broad-spectrum antibiotics, although this may ultimately lead to greater antibiotic resistance in the future. An alternative option is to tailor the antimicrobial regimen based upon the local hospital antibiogram or individual rectal swab cultures performed at the visit prior to prostate biopsy. Other key recommendations are to assess the patient for risk factors for a prostate biopsy infection (such as diabetes, recent antibiotic use and foreign travel) and to counsel patients to seek immediate medical attention at the first sign of an infection.


Transperineal biopsy is another way to biopsy the prostate. Can you outline the advantages and disadvantages of this technique?

In the United States, most prostate biopsies are performed in the outpatient clinic through the rectum (transrectal) using ultrasound guidance. An alternate way to access the prostate for tissue sampling is through the skin of the perineum. Recent studies have suggested that the transperineal approach may reduce the risk of infectious complications. However, unlike transrectal biopsy, it is typically performed in the operating theatre with general anesthesia, thus involving greater time and expense. Transperineal prostate biopsies may also involve a greater risk of urinary retention, a situation where the patient is temporarily unable to urinate.


There has been a lot of interest in the use of MRI as a way of reducing 'unnecessary' biopsies. What are your views on this?

MRI technology has advanced substantially in recent years. At New York University, we have a well-established prostate imaging program using a 3 Tesla multiparametric MRI without an endorectal coil. Most patients tolerate the procedure well and it provides a very detailed anatomic view of the entire prostate, including regions that are poorly sampled during a traditional prostate biopsy. Suspicious lesions found on MRI can then be targeted during the prostate biopsy as a way to increase diagnostic yield. MRI may be particularly useful for men with a persistently elevated PSA and previous negative prostate biopsies, as well as for monitoring patients during active surveillance.


You can read more about Stacy by following the link to NYU Langone Medical Centre and you can follow her @loebstacy on Twitter.


Categories: Prostate Cancer

Affiliations

Urology Affiliations

Latest Tweets

Contact Us

  • Nick Brook Urology
    Kimberley House
    89 Strangways Tce,
    North Adelaide,
    Adelaide SA 5006
  • 08 8463 2500
  • 08 8267 3684