Freezing Out Prostate Cancer

Remember that classic 1950s horror movie, The Blob? Steve McQueen figures out that the creature is vulnerable to cold, and manages to finally do it in by putting it “on ice.”

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Now re-imagine it for today, except Steve McQueen is your urologist and the creature is prostate cancer.

In a procedure known as cryotherapy, extremely cold temperatures are applied to prostate cancer cells to kill them. It's rarely your doctor's first line of attack, but it stands to become more popular now that a new technique that gives doctors more accuracy has been developed.

In “traditional” cryotherapy, your doctor would use transrectal ultrasound to guide several hollow needles through the skin between the anus and scrotum and into the prostate while you were under either general or epidural anesthesia. Then, compressed argon gas chilled to around -40 degrees Celsius is pumped through the needles to freeze and destroy the prostrate. The doctor monitors what is happening inside you by way of the ultrasound.

Most patients who undergo cryotherapy return home the same day; the procedure usually takes around two hours. It is usually offered to prostate cancer patients who have undergone unsuccessful radiotherapy but are not suitable for High Intensity Focused Ultrasound. This last is not an option if your prostate is too big, or if the cancer is at the front of the gland, or if there is too much build up of calcium which blocks the sounds waves.

The new procedure swaps the ultrasound out in favor of magnetic resonance imaging. Using MRI, your doctor can watch ice develop on the needles in 3D and in real-time. This provides much more detail and amps up the accuracy when destroying tumors through the ability to 'sculpt' balls of ice to cover the affected area. In traditional cryotherapy, doctors can only see the ice grow on the edge of the needles that are facing the ultrasound probe. This lack of precision reduces the procedures overall effectiveness.

The new technique stands to make cryotherapy more popular, but is still unlikely to turn it into one of your doctor's go-to procedures. Side effects include lingering pain and burning sensations, and the need to empty bladder and bowels frequently. Freezing frequently damages the nerves near the prostate that control erections, so erectile dysfunction is even more common after cryotherapy than it is following radical prostatectomy.

 

Sources: The American Cancer Society