A prostate biopsy is the only way to confirm whether prostate cancer is present and, if so, how aggressive it is. There are two main ways to take the samples. Understanding the difference helps you know what to expect and what to ask.
Why a biopsy may be needed
Most men have an MRI scan before a biopsy. If the scan shows a suspicious area, or if other factors such as a rising PSA raise concern, a biopsy is usually recommended. Small samples of tissue are taken with a fine needle and examined under a microscope.
The transrectal approach
In a transrectal biopsy, often called TRUS biopsy, an ultrasound probe is placed in the back passage. The needle passes through the wall of the rectum into the prostate.
Advantages:
- quick, usually around 15 minutes
- done under local anaesthetic
- long experience of its use
Drawbacks:
- because the needle passes through the bowel, there is a higher risk of infection, which can occasionally be serious
- antibiotics are always needed
- some areas of the prostate, particularly at the front, are harder to reach
The transperineal approach
In a transperineal biopsy, the needle passes through the skin of the perineum, the area between the scrotum and the anus. An ultrasound probe in the back passage still guides the needle, but the needle does not go through the bowel.
Advantages:
- much lower risk of serious infection
- better access to all parts of the prostate, including the front
- can be done under local or general anaesthetic
Drawbacks:
- may take a little longer
- some men have more bruising or discomfort in the perineum afterwards
Which is better?
Many UK centres have moved to transperineal biopsy because of its lower infection risk and good access to the whole gland. Modern transperineal techniques can often be carried out under local anaesthetic in a clinic setting, so most men go home the same day. Your specialist will explain which approach is recommended for you and why, taking into account your MRI result, general health and any previous biopsies. Accuracy depends on the skill of the team and on whether the biopsy is guided by MRI, as well as on the route used. NICE guidance on prostate cancer includes recommendations on biopsy approaches.
Targeted and systematic samples
Whichever route is used, the samples may be:
- Targeted: aimed at the area seen on MRI, using the images to guide the needle.
- Systematic: taken in a pattern across the prostate, to check other areas.
Many men have a combination of both. Our article on significant cancer after a negative MRI explains why systematic samples are still sometimes taken.
Before and after the biopsy
Before the test, tell the team if you take blood thinners, have diabetes or have had a urine infection recently. You may be asked to stop some medicines for a few days.
After the biopsy, it is common to notice:
- blood in the urine for a few days
- blood in the semen for several weeks
- mild aching in the perineum
Seek urgent advice if you develop a fever, shivering, difficulty passing urine or heavy bleeding. Prostate Cancer UK has a helpful guide to recovery after a biopsy.
Getting your results
Results usually take one to two weeks. If cancer is found, the report gives a Gleason score and Grade Group, which describe how aggressive it looks. Our prostate cancer page explains how these results guide treatment, and our article on questions to ask your surgeon can help you prepare for the next appointment.
Professor Prokar Dasgupta can explain your biopsy options and results at The London Clinic. Please contact the clinic to arrange a consultation.