Hitting The Bullseye With Prostate Cancer
Missing the Mark
During my second year of residency, one of my co-residents bought a ‘fixer-upper’ in downtown Indianapolis and completely renovated the basement. How she found the time I’ll never know, but what once resembled a bleak, concrete floored chamber from the set of ‘Saw’ was transformed into a pretty impressive home theater and game room.
At one of her first housewarming parties, I got the chance break in her and her husband’s new dartboard. I remember feeling the weight of the dart, staring at the bullseye as hard as I could, and then purposefully launching my missile in a gradual arc until it landed with a SMACK…right into their brand new drywall. A full foot away from my intended target. My co-resident graciously laughed it off, but by the end of the night it looked like someone had fired a load of buckshot into the wall surrounding the dartboard.
Looking back on that night (and many more like it since) I can’t help but reflect that how we’ve been performing prostate biopsies isn’t all that different. Let me explain.
The Prostate Biopsy: Why Oh Why?
When a man is thought to be at risk for having prostate cancer, whether from an elevated PSA or an abnormal prostate exam, the next step is typically a prostate biopsy (see this post for more info). This is a small sampling of prostate tissue that’s supposed to be representative of what’s going on in the prostate as a whole. Biopsies in medicine are extremely common, but prostate biopsies are unique in that they are typically NOT targeted. Instead, urologists follow a general template where the prostate is sampled in 10-12 specific regions. While this has been considered to be the standard of care for decades, there are significant drawbacks to this approach.
In almost every other solid organ, we have fantastic options for imaging that allow us to see and specifically target abnormal areas for biopsy. We do this for kidneys, bladders, adrenal glands, bones, and even the brain. Not so in prostate cancer.
Because the prostate is so dense, most traditional imaging tools just don’t work very well. It’s almost like the prostate is a black box. CT scans and ultrasounds can show us the shape, size and contour of the prostate – but they can’t really show us what’s going on inside. Each part of the prostate looks similar to the rest (generally speaking) so it’s been hard to say if something looks cancerous or not based on imaging along. As a result, we’ve been stuck performing template biopsies – hoping that if there IS something there we’ll get lucky and sample it. We might as well be throwing a dart at a wall with our eyes closed.
But what if a man has a big prostate and cancer has more places to hide? What if a man has a prostate cancer growing in an abnormal location that isn’t getting sampled? These are dilemmas that urologists and their patients have been grappling with for decades.
MRI Fusion: A New Standard?
Fortunately, urologists now have a new tool in the fight against prostate cancer: high powered magnetic resonance imaging (MRI). MRI itself is not a new technology, but higher powered magnets are now allowing us to see inside the prostate for the first time. These MRI images can then be superimposed upon real time ultrasound through a process known as MRI Fusion – allowing urologists to identify and target any concerning areas for biopsy like never before.
MRI fusion is still an emerging technology (it only became publicly available ~3 years ago) but it’s gaining increasing traction as more and more urologists adopt this promising skill. Just this past month, the New England Journal of Medicine published one of the first multi-institutional randomized trials comparing MRI fusion to traditional template biopsy. This study included 500 men and showed MRI fusion to be just as safe as traditional biopsy and 50% more likely to diagnose clinically significant cancer. Now this study was far from perfect, but it highlights how fusion biopsy appears to be establishing itself as a new standard of care in prostate cancer.
What does this mean for me as a patient?
If you’re a patient and your urologist thinks you might benefit from a prostate biopsy, ask him about MRI fusion. It may not yet be available where you live (and sometimes insurance can balk at paying for the MRI), but it’s worth considering if it is.
If you’re patient, have you ever undergone a prostate biopsy? What was your experience like? If you’re a provider, what do you think of MRI fusion? Has it been adopted into your practice yet?