Prostate Biopsy
(TRUS guided prostate biopsy)

A prostate biopsy is a test to remove small samples of prostate tissue to be examined under a microscope. For a prostate biopsy, a thin needle is typically inserted through the rectum, under the guidance of an ultrasound (TRUS) probe. The tissue samples taken during the biopsy are examined for cancer cells by the pathologist.

A biopsy may be done when a blood test shows a high level of prostate specific antigen (PSA) or after a physical examination finds an lump in the prostate.

Why it is done

A prostate biopsy is done to determine:

  • Whether a lump found in the prostate gland is cancer.
  • The cause of a high level of prostate-specific antigen (PSA) in the blood.

How to prepare

Tell your doctor if you:

  • Have had any bleeding problems.
  • Are allergy to any medications, including anesthetics.
  • Take any medications regularly. Be sure your doctor knows the names and doses of all your medications.
  • Are taking any blood-thinning medications, such as warfarin, heparin, enoxaparin, aspirin, clopidogrel, ibuprofen, or other nonsteroidal anti-inflammatory drugs (NSAIDs).

A blood test (coagulation profile or PT/APTT/INR) is performed before the biopsy to ensure normal blood clotting ability of the body. An enema is usually given before the biopsy.

How it is done

Prostate biopsy is usually done as a daycare procedure with about half a day spent in the hospital. Before your prostate biopsy, you will be given antibiotics to prevent infection. You will be asked to change to hospital clothing. Transrectal ultrasound (TRUS) is used to guide the needle to the correct biopsy location. A prostate biopsy is usually done with a spring-loaded needle. The needle quickly enters the prostate gland and removes a tissue sample. Multiple tissue cores (12 – 14) are removed to represent all the areas of the prostate. Additional areas may be sampled if any suspicious area is has been detected on the prostate MRI performed earlier. A transrectal biopsy procedure usually takes about 5 minutes.

How it feels

For a transrectal biopsy, you may feel pressure in the rectum while the ultrasound probe or guiding finger is in place. You also may feel a brief, sharp pain as the biopsy needle is inserted into the prostate gland. Usually several biopsy samples are collected. With local anesthesia, most patients are able to tolerate this procedure well.

Following the biopsy, you will be asked to avoid strenuous activities for about 4 hours. You may experience some mild discomfort in the biopsy area for 1 to 2 days after the biopsy and may notice some blood in your urine. Also, you may have some discoloration of your semen for up to one month after the biopsy. If you had a transrectal biopsy, you may experience a small amount of bleeding from your rectum for 2 to 3 days after the biopsy.

Biopsy Needle

A prostate biopsy has a slight risk of causing problems such as:

  • Infection - Usually, taking antibiotic medication before the biopsy prevents an infection from developing.
  • Bleeding - This may occur from the rectum or the urinary passage, mixed with urine or separately. You may see some clots. Usually it resolves on its own in 2 - 3 days.
  • Difficulty in passing urine due to swelling of the prostate or bleeding.
  • An allergic reaction to the anesthetic medications used during the biopsy.

After the biopsy

Report to the emergency immediately if you:

  • Have heavy bleeding or bleeding continues longer than 2 to 3 days.
  • Have increased pain.
  • Have a fever.
  • Are unable to urinate within 8 hours.

A prostate gland biopsy is a test to remove small samples of prostate tissue to be examined under a microscope. Results are usually available within 5 days.

Normal The prostate gland tissue samples appear normal under the microscope, with no signs of infection or cancer.
Abnormal Cancer cells (prostate cancer) or signs of infection (prostatitis) are found.

If cancer cells are present, a grade (Gleason score) will be given, which your doctor will discuss with you. The Gleason score is considered a tool for predicting how aggressive the cancer is.

What affects the test

Factors that can interfere with your test or the accuracy of the results include:

  • The biopsy may not contain enough tissue to make a diagnosis.
  • A chance that a cancer may be missed since the biopsy takes a small amount of tissue.

What to think about
  • Normal prostate biopsy results do not completely rule out cancer.
  • A prostate gland biopsy does not cause problems with erections and will not make a man infertile.
Summary (Prostate biopsy at a glance)

Prostate biopsy is best performed under transrectal ultrasound guidance using a spring-loaded biopsy device coupled to the transrectal probe. The patient is prepared with an enema and an antibiotic. The lubricated ultrasound probe is inserted into the rectum. Some lubricating gels include a topical anesthetic. Patients are positioned on their side for this procedure. The surgeon will first image the prostate using ultrasound, noting the prostate gland's size and shape and whether or not any other abnormalities exist, the most common of which are shadows which might signify the presence of prostate cancer. However, not all prostate cancers are visible. Using the spring-loaded biopsy device attached to the ultrasound probe, the surgeon performs multiple biopsies of the prostate gland. Generally, 12 to 14 (or more, depending upon the size of the prostate gland and the prior PSA and biopsy history of the patient) biopsies will be performed. Each biopsy removes a cylinder of prostate tissue approximately 3/4 inch in length and 1/16 inch in width. The entire procedure takes 5 to 7 minutes.

The biopsy tissue taken will then be examined by a pathologist (a physician who specializes in examining human tissue to determine whether it is normal or diseased). The pathologist will be able to confirm if cancer is present in the biopsy tissue. If cancer is present, the pathologist will also be able to grade the tumor. The grade indicates the tumor's degree of aggressiveness—how quickly it is likely to grow and spread. The Gleason grading system is the most widely used system. In this system, the majority tumor pattern is assigned a score from 3 to 5 and the minority pattern is similarly assigned a score, using the same scale. The majority and minority scores are added together to give a Gleason sum ranging between 6 and 10. A score of 6 designates low aggressiveness, 7 moderately aggressive and scores of 8 to 10 highly aggressive.

The transrectal ultrasound guided prostate biopsy is usually well tolerated. Blood in the ejaculate (hematospermia) and blood in the urine (hematuria) occur in most patients. High fever is rare, occurring in only 1 to 2 percent of patients. The antibiotic is continued for at least 48 hours after the biopsy procedure.