The standard of care for prostate biopsy has been evolving in recent years. Currently, most prostate biopsies are done via ultrasound guidance.
An ultrasound probe is placed which allows visualization of the prostate and then needle biopsies are selected. Usually, these are done in a somewhat random fashion, in an attempt to get a representative sampling of the prostate. Sometimes, the ultrasound will be useful to identify suspicious areas, but most often, the biopsies are random.
In clinical practice, we know that at least 25% of the time a negative biopsy is incorrect, and there is cancer present that was not sampled. Sometimes, this can be because there is a small amount of cancer, but it also could be that the cancer is in a place that is not usually sampled.
As urologists, we have been looking for a more accurate way to do prostate biopsy. Our colleagues in other specialties have been successful with guided biopsy technology with liver and breast biopsies.
In the past 5 years, use of prostate MRI as an adjunctive test has gained some momentum. It allows us to get a more accurate picture of the prostate prior to doing an invasive procedure. The trick has been trying to combine the MRI pictures with the biopsy process. This is no easy feat, considering the cost and size of the MRI scanners.
Now we are able to use technology called MRI-Fusion Trans Rectal Ultrasound Prostate Biopsy. This allows us to use the MRI imaging to identify suspicious lesions. Software allows us to overlay the targets of concern over the ultrasound images during the office procedure in real time.
Here is how it works: In the appropriately selected patient, the MRI is completed and read by a radiologist trained in prostate MRI. If targets are identified, then software is used to outline the targets. That information is loaded into the ultrasound machine in the office on a separate day. The targets, which may have previously been invisible, appear literally as red circles during the prostate ultrasound. The biopsies are then taken in the usual way. The term fusion refers to the combination of the two radiologic modalities—MRI and ultrasound.
MRI fusion biopsy is not necessary for all patients, but there are some patients who may benefit including:
- A patient who has been diagnosed with a low risk prostate cancer doing active surveillance
- A patient with persistently elevated PSA
- A patient with a PSA that is rising even after a negative biopsy
- A patient who has abnormal genetic markers
Urology Specialists of Oregon was the first private practice group in the state to use fusion biopsy technology. The procedure is completed in the office. Other than the MRI, there is minimal increased cost to do the procedure. As always, a facility fee is not charged at Urology Specialists of Oregon.