What is the test?
If your doctor is concerned from your rectal exam or from blood tests that you could have a cancer in your prostate, he or she is likely to recommend transrectal ultrasound and biopsy. This test allows a urologist to take samples from several places in your prostate so that these cells can be examined for cancer.
How do I prepare for the test?
There is often no special preparation for this test, although some doctors will recommend that you use an enema before the test to empty your rectum of stool. (An enema means squirting fluid into your rectum through a short tube. This causes your rectum to react by making you have a bowel movement.)
Tell your doctor if you have any allergies, especially to antibiotics.
What happens when the test is performed?
Most patients are asked to lie on their side for this test, with their knees bent up to their chest. The sensor of an ultrasound machine will be gently pushed into your rectum. This sensor is a short rod about the width around of two fingers. It is covered with a clear jelly that helps it move more easily into the rectum. When the sensor is put into the rectum, you will feel some pressure that resembles the feeling you have before a bowel movement. This sensor gives off sound waves and detects the waves that bounce back from the prostate, allowing the ultrasound machine to create a black and white picture showing your prostate on a TV screen.
After your prostate is examined using the ultrasound, this ultrasound sensor will be pulled out of your rectum and replaced with a slightly smaller one. The smaller sensor also does ultrasound but it has a small tube attached to its side called a “needle guide.” Your doctor will use the ultrasound to point the needle guide at specific parts of your prostate. A special needle that is spring-loaded is released from the end of the needle guide. The spring-loading allows this needle to move into and out of the prostate very quickly, while the needle collects a sample. Most patients do feel some discomfort from each biopsy, but because the needle moves so quickly it will last only for a second. Usually a patient has 6-8 samples collected, each from a different part of the prostate. Then the probe is removed.
Many doctors will give you antibiotics (sometimes with a combination of an injection and pills) at the end of this procedure to prevent infection.
What risks are there from the test?
Many patients notice some blood in their urine or stool for a day or two after the biopsy. The only risk to be concerned about in a rectal biopsy is the possibility that you could get an infection in the prostate following the procedure. Most doctors will treat you with antibiotics to prevent this kind of infection.
Must I do anything special after the test is over?
Call your doctor if you develop a fever after this test.
How long is it before the result of the test is known?
Your prostate samples will be examined under a microscope by a pathologist who will check them for cancer. This requires several days.