Prostate Center Paris

Transperineal prostate biopsy: safe diagnosis and reduced risks

Prostate biopsy is a crucial examination for confirming or ruling out the presence of prostate cancer. Although it has revolutionized the management of associated cancers, the procedure carries significant risks of complications.

Generally, the prostate biopsy is performed via the transrectal route, as the sampling needle crosses the rectal mucosa, which is rich in faecal bacteria, causing numerous cases of infection, some of them serious. To offset this risk of infection, new approaches to prostate access have been developed thanks to technological advances, notably transperineal prostate biopsy.

This new generation of prostate biopsy offers efficacy results similar to those of transrectal biopsy, but with reduced risks. It has aroused great interest in the medical field and has been the subject of much research. We will explore the conclusions drawn from 20 years of scientific studies.

Prostate biopsy: an essential diagnostic tool for detecting cancer

Every year in the United States, over a million prostate biopsies are performed, making them an essential and virtually unavoidable step in the diagnosis of prostate cancer. The biopsy is generally performed transrectally, under ultrasound guidance: a needle is inserted through the rectal wall to the prostate to take a tissue sample. However, on this journey, the needle can carry bacteria from the rectum into the urinary tract, leading to complications such as cystitis, prostatitis or epididymitis. To prevent infection, antibiotics are prescribed in preparation for the biopsy. However, the rate of infection after transrectal prostate biopsy is estimated at 7%, and the rate of post-biopsy sepsis ranges from 0.3% to 3.1%.

To reduce these adverse effects, a percutaneous approach through the skin of the perineum has been developed over the last few decades. The biopsy needle is inserted through the skin of the perineum, which is less exposed to bacteria, and then directed at the prostate. This method considerably reduces the risk of infectious complications. Data from recent studies on transperineal prostate biopsy show very encouraging results in terms of low rates of infectious complications, ranging from 0% to 1%. It should be emphasized that routine administration of antibiotics in preparation for the procedure is not necessary in most cases.


The different types of ultrasound/ultrasound-guided transperineal prostate biopsy

Protocol and indications

Ultrasound-guided transperineal biopsy of the prostate is a minimally invasive procedure used in the diagnosis of prostate cancer. It comprises three main stages: localization of suspicious lesions on ultrasound, insertion of a biopsy needle into the lesions, avoiding noble tissues, and aspiration of a prostate fragment for laboratory examination. The procedure is performed in the clinic, under local anaesthetic for the patient's comfort, and may be accompanied by light sedation on request.

Two main methods are used to perform a transperineal biopsy of the prostate: the "stepper" method and the "freehand" method:

  1. Stepper" method The "stepper" method involves the use of a mechanical device to guide the biopsy needle. This new-generation technique offers extremely precise control of the needle's position when taking tissue samples. It thus guarantees highly precise targeting of suspect lesions.
  2. Freehand" method The "freehand" method relies on the physician's expertise to guide the biopsy needle in real time, based on ultrasound images. This method is just as reliable as the "stepper" method, and offers the advantage of giving the practitioner a degree of flexibility in choosing which lesions to sample.

At the Xper® Prostate Center, our specialists have mastered both techniques and can choose the one best suited to each patient's specific needs.

Transperineal biopsy of the prostate is particularly recommended in the following cases, given its safety and the use of the transperineal route instead of the rectal route:

  • History of infection after previous transrectal biopsy
  • History of prostatitis
  • Inflammatory bowel disease
  • Rectal bleeding after a previous biopsy
  • Negative anterior transrectal biopsy with suspicion of anterior prostate tumor.

Transperineal prostate biopsy: What are the results?

While transperineal biopsy of prostate cancer is safer, it is essential that it also delivers reliable results. Indeed, it would not be beneficial to reduce the risk of infection at the expense of prostate cancer detection.

Estimates of sensitivity (ability to detect a lesion as prostate cancer) and specificity (ability not to misdiagnose prostate cancer) of transperineal biopsy are identical to those of the transrectal approach, if not better. In fact, the transperineal approach enables samples to be taken from the anterior part of the prostate, which can be more difficult with the transrectal approach. Thus, transperineal biopsy reduces the risk of failure to detect lesions located in the anterior parts of the prostate.

With equivalent efficacy and superior safety, transperineal prostate cancer biopsy has proven to be the most effective and reassuring method of performing a prostate biopsy. In combination with clinical and biological findings, prostate biopsy will confirm the diagnosis of prostate cancer or, if negative despite an elevated PSA level, point to prostate hypertrophy. Prostate hypertrophy, also known as prostate adenoma, is characterized by an increase in the size of the prostate, causing urinary symptoms and elevated PSA levels, without presenting any risk of cancerous metastases.

Advantages of MRI prior to biopsy

Recently, European guidelines for the diagnosis of prostate cancer have changed: it is now recommended to perform an MRI scan prior to prostate biopsy. Prostate MRI provides an initial non-invasive, non-irradiating mapping of the prostate, helping doctors to decide whether to proceed with a biopsy by enabling them to determine a patient's risk score. Thanks to the use of high-resolution MRI, many men could receive a negative diagnosis of prostate cancer, avoiding the need for a prostate biopsy and the associated risk of complications and discomfort.

If the diagnosis of prostate cancer cannot be ruled out by MRI, a transperineal biopsy can be performed. Combining the two techniques not only improves diagnostic accuracy, but also reduces the discomfort caused by prostate cancer biopsy. The high-quality images provided by MRI enable complete mapping of the prostate and potentially cancerous lesions, facilitating targeting during prostate biopsy and improving therapeutic results.

Transperineal prostate biopsy: What are the risks and complications?

As with any procedure, transperineal biopsy of the prostate presents a certain risk of complications. Scientific research has focused on assessing the quality of the results obtained, as well as the associated risks, in order to determine its superiority over other biopsy methods.

The risks and complications associated with transperineal biopsy are mainly due to the introduction of the needle into the skin, and include:

  1. Temporary presence of blood in urine or semen: Since the prostate surrounds the urogenital carrefour, any biopsy of the prostate will result in bleeding, leaving traces of blood in urine or semen. This complication is frequent but not serious, and resolves itself in the weeks following the operation.
  2. Bruising at the skin puncture site: The needle may touch small blood vessels, resulting in bruising. The transperineal route has the advantage of leaving this bruise on the skin of the perineum rather than in the rectal cavity. It disappears on its own in the weeks following the procedure.
  3. Temporary erectile dysfunction: After prostate biopsy, short-term erectile dysfunction may occur in 5 % of patients. This problem resolves naturally as the prostate heals.
  4. Urinary retention requiring catheterization: In less than 1 % of cases, transperineal biopsy may result in swelling at the urogenital junction, leading to urinary retention. In such cases, a temporary catheter may be required to allow urine to pass.
  5. Risk of infection, such as sepsis: Cases of sepsis after prostate biopsy are rare, around 0.2 %. However, this risk is kept under control by prophylactic antibiotics. This figure should also be compared with the infection rates associated with transrectal biopsies, which oscillate around 1.5 to 2 % according to the latest studies.

An additional advantage of transperineal prostate biopsy is the absence of rectal bleeding. Unlike transrectal biopsy, the needles do not come into contact with the rectal wall.

Research into transperineal prostate biopsy shows that complications are limited, making it the safest method of intervention. To assess the benefit/risk balance, its efficacy has been tested in further studies.