Prostate biopsy

A prostate biopsy is a procedure to remove samples of suspicious tissue from the prostate. The prostate is a small, walnut-shaped gland in males that produces fluid that nourishes and transports sperm.

Transrectal ultrasound guided (TRUS) biopsy of the prostate

The process of TRUS biopsy takes around 10 minutes to perform. It involves a finger based examination of the prostate followed by insertion of an ultrasound probe into the rectum. Local anaesthetic is injected through the front wall of the rectum using a small needle to reduce sensation. This is often not felt. Prostatic measurements are taken however imaging alone is not accurate enough to distinguish the source of PSA elevation. A guide attached to the probe allows control of the biopsy device. When the biopsy device is activated it makes a clicking noise delivers a short lived “thud” in the rectal area. The biopsies have been likened to being flicked with a rubber band.

12 biopsy cores are taken on a “random” basis from the prostate. In reality these cores are directed using ultrasound imaging in a systematic fashion. These biopsies are designed to provide a representative sample however they do not remove the entire prostate.

As the biopsies are taken through the rectal wall there is a small risk of either bleeding or infection. Antibiotics are given routinely to reduce the risk, starting the day prior to biopsy and continuing for one day afterwards. The risk of side effects significant enough to require admission to hospital is in the order of 2%. Blood thinners such as warfarin, clexane and clopidogrel should be stopped prior to the procedure however this process should be discussed first as alternative therapy may be required to avoid complications. Aspirin at a moderate dose (300mg/day) is usually OK to continue for the biopsy. Other preparation such as bowel cleansers is unnecessary.

Following the biopsy, strenuous exercise is avoided for the first week. Pathological results generally take at least a week to become available as various staining processes need to be undertaken. A follow-up urology visit is routine to discuss the results of the biopsy and what these will mean in terms of either treatment or the need for future screening.

Transperineal Prostate Biopsy (TPPB)

The alternative to prostate biopsy through the rectum is using an approach through the skin of the perineum (behind the scrotum and in front of the anus). This has the benefit of a significantly reduced risk of infection and bleeding from the bowel after the procedure.

Typically this approach is done under general anaesthetic which makes it painless but has the downsides of increasing cost and requiring a recovery day for the effects of the anaesthetic to wear off (when no driving or operating machinery is necessary).

The TPPB method is of particular importance in accessing the front of the prostate which is more difficult to reach via the transrectal route.