|‘We are using state of the art imaging techniques (mpMRI, fusion biopsy and PSMA-PET/CT and PSMA-PET/MRI data) for selecting suitable patients for focal therapies and for follow-up after procedures.
Cryotherapy (also called cryoablation) is the use of very cold temperatures to freeze and kill prostate cancer cells as well as most of the prostate. During cryotherapy, thin metal probes are inserted through the skin and into the prostate. The probes are filled with a gas that causes the nearby prostate tissue to freze, while sparing surrounding structures such as the bladder and urethra
Cryotherapy might be used to treat early-stage prostate cancer that’s confined to one part of the prostate if other treatments aren’t an option for you. Cryotherapy for prostate cancer can also be used when the cancer has returned after initial treatment.
In the past, cryotherapy for prostate cancer was associated with more long-term side effects than were other prostate cancer treatments. Advances in technology have reduced these side effects.
It is well known that when human tissue is exposed to temperatures below freezing that tissue damage occurs. With temperatures falling to -7° to -10° Celsius extra- cellular water (water in tissue but outside cells) begins to crystallize. This in turn increases the concentration of electrolytes in the extracellular fluid and begins to draw water from inside cells. As the temperature drops to °-15C ice crystals begin to form inside the cells. Cell membranes are damaged, and cells are destroyed. When tissue is cooled to -40°C, all metabolic processes stop.
Cryoablation in Clinical Practice
The original indication for cryoablation of the prostate was for salvage therapy in prostate cancer patients who had recurred after either external beam radiotherapy or brachytherapy. However, now prostate cryotherapy is also indicated for primary treatment of prostate cancer.
A typical patient is an older patient, particularly one with voiding symptoms that prohibit the safe application of radiation. Other indications would include lower risk cancers, and in patients with morbidities that would make surgery exceedingly risky.
Why it’s done
Your doctor may recommend cryotherapy for prostate cancer as an option at different times during your cancer treatment and for different reasons. Cryotherapy might be recommended:
- As the initial treatment for cancer if your cancer is confined to your prostate and other treatments aren’t an option for you
- As a treatment for prostate cancer that comes back after your initial treatment
Cryotherapy for prostate cancer generally isn’t recommended if you:
- Previously had surgery for rectal or anal cancer
- Have a condition that makes it difficult or impossible to monitor the prostate with an ultrasound probe during the procedure
- Have a large tumor that can’t be treated with cryotherapy without damaging surrounding tissue and organs, such as the rectum or bladder
Researchers are studying whether cryotherapy to treat one part of the prostate might be an option for cancer that’s confined to the prostate. Termed focal therapy, this strategy identifies the area of the prostate that contains the most aggressive cancer cells and treats that area only. Studies have found that focal therapy reduces the risk of side effects.
These needles are placed through the perineal skin between the scrotum and rectum under ultrasound guidance using a special template, much the way that seeds are placed for brachytherapy. Two freeze-thaw cycles are completed, after which time a catheter is placed in the bladder. Prostate cryotherapy takes around an hour to perform, and there is little pain afterward. For the first hour or two, a patient will commonly feel an urge to urinate which slowly dissipates. There can be blood in the urine of course, and as stated scrotal swelling is very common and should not concern the patient. The patient will be asked to remove his catheter six days later and see your doctor for a voiding trial the next day. Occasionally, especially in those with pre-existing urinary difficulties, the catheter must be replaced temporarily.
Side effects of cryotherapy for prostate cancer can include:
- Erectile dysfunction
- Blood in the urine
- Loss of bladder control
- Pain and swelling of the scrotum and penis
- Bleeding or infection in the area treated
Rarely, side effects can include:
- Injury to the rectum
- Blockage of the tube (urethra) that carries urine out of the body
How you prepare
One day prior to the procedure, the patient is instructed to start taking a quinolone antibiotic (levaquin or cipro), undergo a bowel preparation, and assume a low fiber diet. On the day of the procedure, either general or spinal anesthesia is required.
What you can expect during cryotherapy for prostate cancer
Cryotherapy for prostate cancer is done in the hospital. You may be given a drug called a general anesthetic to put you in a sleep-like state. Sometimes a regional anesthetic is used so that you’ll remain aware of your surroundings but won’t feel anything in the treatment area.
Once the anesthetic takes effect, your doctor:
- Places an ultrasound probe in your rectum.
- Places a catheter inside the tube (urethra) that carries urine out of the body. The catheter is filled with a warming solution to keep the urethra from freezing during the procedure.
- Inserts several thin metal probes or needles through the area between the scrotum and the anus (perineum) into the prostate.
- Watches the images generated by the ultrasound probe to ensure correct placement of the needles.
- Releases a gas to circulate through the probes or needles that causes freezing in the prostate tissue.
- Monitors and controls the temperature of the needles and the amount of freezing within the prostate gland.
- May place a catheter into your bladder through your lower abdomen to assist in draining urine after cryotherapy.
After cryotherapy for prostate cancer
You’ll likely be able to go home the day of your procedure, or you may spend the night in the hospital. The catheter may need to remain in place for about two weeks to allow for healing. You might also be given an antibiotic to prevent infection.
After the procedure, you may experience:
- Soreness and bruising for several days where the probes or needles were placed
- Blood in your urine for several days
- Problems emptying your bladder and bowels, which usually resolve over time
How is follow-up after the treatment?
PSA levels should be checked every 3 months.
In order to check if your prostate cancer is cured or not, you will have prostate MR in specific periods after treatment.
In case of any clinical necessity prostate biopsy might be used to confirm.
If cancer cells are existent, a second cryotherapy treatment or other focal therapy procedures can be used.