Prostate biopsy is a procedure in which small hollow needle-core samples are removed from a man's prostate gland to be examined microscopically for the presence of cancer. It is typically performed when the result from a PSA blood test rises to a level that is associated with the possible presence of prostate cancer, together with an abnormal digital rectal examination with symptoms of lower urinary symptoms called LUTS. PSA screening is controversial as PSA may become elevated due to non-cancerous conditions such as a benign enlargement of the prostate (BPH, benign prostatic hyperplasia), by infection, or by manipulation of the prostate during surgery or catheterization; and many prostate cancers detected by screening develop so slowly that they would not cause problems during a man's lifetime, making the complications due to treatment unnecessary.
Prostate biopsy is usually done as an outpatient, it requires a local anaesthetic; some men do report discomfort during the biopsy. The most frequent side effect of the procedure is blood in the urine or stool for several days or blood in the ejaculate possibly for several weeks afterwards. These side effects are usually self-limited and do not require additional treatment.
Ultrasound-guided prostate biopsy
The procedure may be performed transrectally, through the urethra or through the perineum. The most common approach is transrectally. The most common method of prostate biopsy as of 2014 was transrectal ultrasound-guided prostate (TRUS) biopsy.
Extended biopsy schemes take 12-14 cores from the prostate gland through a thin needle in a systematic fashion from different regions of the prostate.
Antibiotics are usually prescribed to minimize the risk of infection. In the transrectal procedure, an ultrasound probe is inserted into the rectum to help guide the biopsy needles. A local anesthetic is then administered into the tissue around the prostate. A spring-loaded prostate tissue biopsy needle is then inserted into the prostate, making a clicking sound. If local anesthetic is satisfactory, discomfort is minimal.
MRI-guided targeted biopsy
Prostate cancer cannot be seen on ultrasound due to poor soft tissue resolution. However, multi-parametric magnetic resonance imaging (mpMRI) has since about 2005 been used to better identify and characterize prostate cancer.
MRI-guided prostate biopsy appears to be superior to standard TRUS-biopsy in prostate cancer detection.
Side effects of prostate biopsy may include:
rectal pain or discomfort (very common)
burning when passing urine (very common)
bloody urine for 2-3 days (very common)
infection of skin or urine (1-8%)
infection of skin or urine requiring hospitalisation and intravenous antibiotics (1-4%)
The tissue samples are then examined under a microscope to determine whether cancer cells are present, and to evaluate the microscopic features (or Gleason score) of any cancer found. Gleason score, PSA, and digital rectal examination together determine clinical risk, which then dictates treatment options.