Cryotherapy (also called cryosurgery or cryoablation) is the use of freezing temperatures to kill the prostate cancer cells as well as most of the prostate by cutting off the blood supply. This therapy is not a surgery even though it is referred to as cryosurgery.
Indications for prostate cancer cryotherapy
Most doctors do not prefer cryotherapy as the first option to treat prostate cancer. It is a minimally invasive procedure used as an alternative to treat early-stage prostate cancer in men who for some reason cannot have surgery or radiotherapy. It can also be used in the treatment of prostate cancer resistant to radiation therapy.
The best results of cryotherapy in the treatment of prostate cancer come from proper patient selection. It is ideally suited in patients with low-risk tumor features (ie, serum prostate-specific antigen (PSA) level ≤10 ng/mL, diagnostic biopsy Gleason score ≤6, and clinical stage T1c or T2a).
Tests before the cryotherapy procedure
The patient is subjected to certain tests before he can be taken up for Cryotherapy.
- A pre-procedure prostate-specific antigen (PSA) test is done for assessing the procedural risk if any. It also helps in comparing it with PSA levels after treatment
- Urine culture
- Complete blood cell (CBC) count with platelet count
- Coagulation tests (ie, prothrombin time and activated partial thromboplastin time)
Cryotherapy procedure and how it works in prostate cancer
Cryotherapy is done under spinal or epidural anesthesia or general anesthesia.
Under the guidance of the transrectal ultrasound, the doctor guides several hollow probes (needles) through the perineal skin into the prostate. He then passes very cold gases (argon or nitrogen gas) through the needles to freeze and destroy the prostate. This is exchanged with helium gases to cause a freezing and warming cycle.
What happens is that argon rapidly cools the probe tip to minus 187°C (–304.6°F) and then it can be rapidly exchanged with helium at 67°C (152.6°F) to bring about active thawing.
The ultrasound helps the doctor in targeting the right area and protecting the nearby tissues from damage.
The cryoprobes are placed bilaterally in the anteromedial, posterolateral, and posteromedial regions of the gland.
Freezing rapidly extracts heat from the gland due to which there is an instantaneous formation of ice crystals. This causes the rupture of the cell membranes and, ultimately, cell death.
The frozen dead tissue thaws, the phagocytes clear up the dead cells, which are then absorbed by the body.
To prevent the urethra from freezing, the doctor passes warm water through the catheter placed in the urethra during the procedure. The catheter is placed in the urethra for weeks after the procedure to help drain the bladder of urine.
It takes about two to three weeks for patients to fully recover from cryotherapy. Patients will have to refrain from physically laborious activity to avoid any complications
There aren’t enough long-term studies done for cryotherapy use in prostate cancer. It does seem to offer some benefits and advantages over surgery and radiotherapy especially in early-stage prostate cancer.
- For example, it is minimally invasive and is done under spinal or epidural anesthesia while surgery requires the use of general anesthesia (GA). This is of great advantage in elderly people and those suffering from heart disease, lung disease, and diabetes because the risk of GA complications in such patients is high.
- The patient may rarely require an overnight stay in the hospital.
- It is less invasive than surgery, because of which there is less blood loss.
- The recovery period is shorter
- There is less pain.
However, not much is known about the long-term effectiveness of cryotherapy.
Contraindications for cryotherapy
- Cryotherapy is not used in men with very large prostate glands because of the difficulty in achieving uniform freezing throughout the gland.
- In patients at high risk for lymph node metastasis
- Patients who have a history of a previous transurethral resection of the prostate (TURP)
- Patients with symptoms of urinary obstruction
- Those with any major rectal pathology
- Men with a history of abdominoperineal resection surgery for rectal cancer and rectal stenosis,
In the past, cryotherapy for prostate cancer was known to cause more serious long-term side effects as compared to other prostate cancer treatments.
Modern technology has greatly improved the technology of this procedure and reduced these side effects.
However, long-term sexual dysfunction is still seen in many men following cryotherapy for prostate cancer.
Other side effects include:
- Pain and soreness at the needle injection sites
- Blister formation
- Pelvic and rectal pain
- Urethral stricture
- Loss of bladder control
- Blood in the urine for the first two days after the procedure
- Swelling of the penis or scrotum
- Freezing might also affect the bladder and rectum, which can cause pain, burning sensations, and the frequent need to clear the bladder and bowels.
- Erectile dysfunction is common after cryotherapy because of damage to the neighboring nerves that control erection.
- Rarely, urinary incontinence or fistula may develop.