Transperineal MRI-fusion Targeted Prostate Biopsy

What is a transperineal MRI-fusion prostate biopsy?

A prostate biopsy is the procedure by which small tissue samples are taken from the prostate gland and examined under the microscope by a pathologist to determine whether cancer cells are present. A biopsy is recommended when there is a clinical suspicion of prostate cancer — for example, when the PSA blood test is elevated, when the PSA is rising over time, or when an abnormality is identified on an MRI scan.

Transperineal MRI-fusion targeted biopsy combines two technologies to improve accuracy. First, a multiparametric MRI (mpMRI) scan is carried out before the procedure. The MRI images are then electronically fused with real-time ultrasound during the biopsy itself, allowing precise targeting of any suspicious areas identified on the MRI — while also ensuring that systematic samples are taken from all regions of the prostate.

Needles are introduced through the perineal skin (the area between the scrotum and the anus) rather than through the rectum, which significantly reduces the risk of infection.

Who needs a prostate biopsy?

A prostate biopsy is recommended in men in whom there is a reasonable suspicion of prostate cancer based on:

• An elevated or rising PSA (prostate-specific antigen) blood test
• Suspicious findings on an mpMRI scan (PIRADS 3, 4, or 5 lesions)

The decision to recommend biopsy takes into account the degree of suspicion, the patient’s age and general health, the potential consequences of detecting or missing a cancer, and the patient’s own values and preferences. Not every elevated PSA requires a biopsy; similarly, some mpMRI abnormalities may warrant surveillance rather than immediate sampling.

What to expect: before, during, and after

Before the procedure

You will have already had an mpMRI scan of the prostate, and the images will be reviewed by a specialist radiologist who will score any suspicious areas using the PIRADS classification. A urine sample is checked to ensure there is no active infection. Blood-thinning medication is adjusted as advised. You will be asked to fast before the procedure because a general anaesthetic or sedation is used.

During the procedure

You will lie on your back with your legs raised. A thin ultrasound probe is placed in the rectum to visualise the prostate. The MRI images are electronically fused with the live ultrasound in real time. Biopsy needles are passed through the perineal skin — which is cleaned and draped — into the prostate under ultrasound guidance. Typically, 20–30 cores are taken: a systematic set covering all zones of the prostate, plus additional targeted cores from any MRI-suspicious lesions. The procedure takes approximately 30–45 minutes.

After the procedure

Some men have a urinary catheter placed at the end of the procedure, which is removed later the same day once anaesthetic effects have resolved. Blood in the urine, stool, and ejaculate is expected and can last up to three to four weeks — this is a normal consequence of the biopsy and does not in itself require medical attention. You should drink plenty of fluids in the days following the procedure. Avoid strenuous physical activity for one week.

Contact the clinical team promptly if you develop a temperature above 38°C, shaking, severe difficulty passing urine, or worsening pain.

Results and next steps

Biopsy results are typically available within one to two weeks. A clinic appointment is arranged to discuss the findings.

If the biopsy does not detect cancer, the result is interpreted alongside the PSA level, MRI findings, and clinical picture. A programme of regular PSA checks and, if appropriate, repeat MRI may be recommended.

If prostate cancer is detected, the pathologist’s report will describe the cancer grade using the Gleason score and Grade Group system. This, together with the PSA level, the number of positive cores, and staging information, forms the basis of a multidisciplinary discussion about management options. These may include active surveillance, radiotherapy, surgery, or — in selected circumstances — focal therapy. All options will be discussed in detail so that treatment decisions can be made jointly and with a clear understanding of likely outcomes.