What is a prostate biopsy?
A prostate biopsy removes samples of tissue from the prostate in order to diagnose prostate cancer. This is used after an elevated PSA or abnormal DRE. The tissue is examined by a pathologist to determine if cancer is present. Cancer can only be diagnosed by a tissue sample.
During the biopsy, the doctor will take several ‘core’ samples from different parts of the prostate using a fine needle. More and more frequently, ultrasound is used to guide the needle and limit damage to any tissue.
What are the side effects of a prostate biopsy?
- Infection. The most common risk associated with a prostate biopsy is infection. Rarely, men who have a prostate biopsy develop an infection of the urinary tract or prostate that requires treatment with antibiotics.
- Bleeding at the biopsy site. Rectal bleeding is common after a prostate biopsy. If taking blood thinners, talk to the doctor about how to manage them before and after the treatment.
- Blood in your semen. It’s common to notice red or rust coloring in semen after a prostate biopsy. This indicates blood, and it’s not a cause for concern. Blood in semen may persist for a few weeks after the biopsy.
- Difficulty urinating. In some men, prostate biopsy can cause difficulty passing urine after the procedure. Rarely, a temporary urinary catheter must be inserted.
Because of these side effects, it can be a good idea to try to eliminate other possible causes of an elevated PSA or abnormal DRE before undergoing a biopsy.
What kind of prostate biopsy are there?
There are three types of prostate biopsies:
- Transrectal – The most common biopsy procedure, the doctor – with the guidance of an ultrasound device – inserts needles through the wall of the rectum and into the prostate to take six to twelve samples from different zones of the prostate.
- Transurethral – A lighted tiny lens is inserted into the urethra to allow the doctor to see the prostate and then uses a microscopic cutting loop to take samples of tissue.
- Transperineal – The doctor makes an incision in the perineum and inserts a needle to take tissue cores of the prostate.
What new biopsy techniques are out there?
Research is developing on other biopsy techniques that use MRIs. In this technique, doctors combine real-time ultrasound imaging with MRI data to guide a biopsy. A recent study published in the Journal of the American Medical Association that concludes using MRI with ultrasound produces better biopsy results1. This method aims to give a more accurate biopsy result while minimizing side effects including infection, bleeding, and potential damage to the urethra or nerves causing temporary incontinence and/or erectile dysfunction.
For men who have had a negative biopsy, there is a new test called ProMark. This helps to predict whether the next biopsy will also be negative, potentially cutting down on the number of biopsies a man will have to go through.
What happens after a biopsy?
A negative biopsy indicates that none of the biopsy samples found any evidence of prostate cancer. This is usually good news—however, this does not necessarily mean that there is no prostate cancer present. Your doctor may want to continue to monitor your PSA levels or do a repeat biopsy at some point in the future.
A positive biopsy indicates that there is evidence of prostate cancer. This would be considered a diagnosis of prostate cancer. At this point, you should also have some idea of the approximate location, size, and aggressiveness of the cancer. What happens next is a decision between you and your doctor. There are some additional tests you can take to give you a better idea of your diagnosis. For example, genomic tests can help provide information on how likely your cancer is to spread, or how aggressive it is likely to be.
Additionally, imaging tests can be used to determine malignant areas as well as other useful information.
Procedures such as MRI, PET/CT scans and ultrasounds can be used to aid the detection of prostate cancer. These methods, many of them new or under development, can better determine the presence of prostate cancer and help doctors minimize risk of side effects.
An MRI, magnetic resonance imaging, uses a magnetic field to produce clear images that may not be seen clearly with an X-ray or pictures derived from ultrasounds. It is painless and usually takes about 45 minutes to complete. After prostate cancer has been confirmed by a biopsy, an MRI is useful in enabling doctors to determine malignant areas. Some research has even suggested MRIs can help predict prostate cancer recurrence.
Most MRI machines are confining as the patient is put into a tube like tunnel for the test. This is called a closed MRI. Some people, particularly those with claustrophobia, find it difficult to have the test in the closed machine and can seek to have an open MRI. If an open MRI is not accessible and the test must be done, ask the physician for medication to help reduce anxiety before the test.
A PET (or a positron emission tomography) scan for prostate cancer is noninvasive and uses a nuclear imaging technique to best determine if and how far cancer has spread beyond the prostate by using radioactive materials that can diagnose and even treat the disease. After the substances are released, the PET scanner machine is passed over the body to determine any cancer spread.
Combining computed tomography (CT) with PET increases accuracy of diagnosis by using X-rays that are focused from various areas around the patient’s body.