Template Biopsy
A template biopsy is considered the gold standard prostate cancer biopsy. The principle behind this type of biopsy is the use of a grid (template), with tissue samples extracted through holes in the grid. Each hole correlates to numbers and letters, in the same way as grid references are located on maps. This means tissue samples can be taken from the prostate in a very precise and specific way.
Why am I having a template biopsy?
At the Birmingham Prostate Clinic, a template biopsy is the only type of biopsy we use. In other services you may have had, or have been offered, a TRUS biopsy (trans-rectal ultrasound guided). This is the older, standard prostate biopsy, which involves inserting a probe via the rectum and collecting needle samples via the probe.
We no longer use the TRUS biopsy. This is because the TRUS biopsy has a high level of false negatives; this means the result of the biopsy is negative, but cancer is present and has been missed. This is particularly a risk if cancer is located at the front of the prostate. During a TRUS biopsy, the prostate is accessed via the rectum up to the back of the prostate and does not reach sections of the front. Equally, the TRUS biopsy collects fewer tissue samples than the template biopsy (usually six to 12, using an unspecific pattern) achieving a far lower overall level of accuracy. It is carried out under local anaesthetic and many patients find the TRUS procedure uncomfortable and in some cases, painful.
Template biopsy and the way we assess prostate cancer
In our diagnostic pathway, we only use the gold standard template biopsy. This is because of the much higher level of precision it offers and because of the role it has in our diagnostic pathway. We only proceed to biopsy once the following assessments have taken place: the standard PSA (prostate specific antigen) and DRE (digital rectal examination) plus assessments not routinely undertaken in all services, the PCA3 genetic test and enhanced prostate MRI. Therefore, we only proceed to biopsy at a stage when there is a strong indication that cancer is present in the prostate. Consequently, we require a biopsy which is highly accurate and is much less likely to deliver false negatives.
Types of template biopsy
There are broadly two different types of template biopsy: a saturation template biopsy and a targeted template biopsy. The type used depends on the intention of the procedure.
- A targeted template biopsy is used if the intention is to focus on one part of the prostate because previous assessments have identified the location of the significant disease.
- A saturation template biopsy is used if the intention is to assess the whole of the prostate, mapping every part, taking up to 50 tissue samples.
Having a template biopsy: what to expect
We always carry out template biopsies under a general anaesthetic (GA). Although some services use a local anaesthetic for template biopsies, we prefer a GA because it is more comfortable for the patient. In common with all procedures using a GA, this means that you won’t be able to drive for 48 hours, so you will need someone to drive you home from hospital or have make some arrangements for transport.
Once the patient is asleep, a catheter is inserted to show exactly where the urethra is (the tube that carries urine from the bladder to the penis) and this ensures the consultant avoids placing any needles in the urethra.
The consultant is guided by the images from your MRI scan which are mapped against the prostate. Between 20 to 50 needle samples are taken (the number depending on whether you are having a saturation biopsy, which uses a higher number, or a targeted biopsy, the lower number). After all the tissue samples have been taken, the catheter is removed.
The template biopsy procedure takes approximately 20 minutes.
When will I receive the results of my template biopsy?
You will be invited to come into clinic to discuss your results with your consultant about two weeks after your procedure. You will see the same consultant throughout your treatment at BPC and your consultant will explain the results of your template biopsy, what they mean in terms of management and treatment options and all other considerations.
“There is no doubt that a false negative rate of 10 to 30 per cent is challenging and unacceptable for both the patient and urologist. Men who have to endure repeated biopsies face great uncertainty and anxiety. The template biopsy is a very promising and important development for this group of patients.”