Cryoablation is a relatively new, high-tech curative option for the treatment of prostate cancer. Men with newly diagnosed prostate cancer, as well as individuals who have failed radiation therapy, may wish to consider this treatment modality. The relative advantages and disadvantages of cryo as an alternative to radiation therapy or surgical removal of the prostate gland are discussed below.
CRYOABLATION AT JACKSONVILLE PROSTATE CENTER
CRYOABLATION FOR TREATMENT OF PROSTATE CANCER
Men with prostate cancer may wish to consider cryoablation of the prostate gland as definitive curative treatment of their disease. This state-of-the art technology is readily available to men as an alternative to radiation therapy or to surgical removal of the prostate gland.
McIver physicians have treated over 300 men with cryoablation for more than a decade at St. Vincent’s. Our experience suggests a very low complication rate and a cure rate which is equal to radiation therapy.
Initially our procedures were done with the Cryomedical Science liquid nitrogen technology, but therapy is now delivered with the Galil Argon gas system. In early 2007, we obtained Galil’s new Precise system which has now supplanted the Galil SeedNet system which we have utilized for the past 10 years. The Precise system represents a new era of minimally invasive cryotherapy, with streamlining of the computer controlled process and IceVue planning software for preoperative simulation of the procedure to ensure accurate results. The cryoablation process for prostate cancer is done in the hospital but on an outpatient basis. The candidate must be suitable for a 90-minute procedure under general anesthesia. The actual duration is dependent on the size of the gland. With the Precise system up to 25 cryoprobes can be utilized, but most prostates do not require more than 12 to 15 probes. Each probe is an ultra-thin needle of 1.4 mm diameter, placed through the perineum into the prostate gland with ultrasound guidance. Compressed Argon gas is delivered through the probe, generating a computer controlled ice ball which is visualized and monitored with ultrasound. Thermocouples placed into the gland and surrounding areas assure that appropriate lethal temperatures are achieved in the prostate and that adjacent tissues are not damaged by the freeze. A closed circuit warming catheter protects the urethra from damage as water warmed to 43° centigrade is circulated through the catheter.
Pain from the cryoablation procedure is minimal. Each patient has a suprapubic catheter placed while under anesthesia since the prostate gland swells temporarily with the lethal freeze. After several days the catheter can be clamped and urination initiated through the urethra. The suprapubic catheter is generally removed at the first post-operative office visit, 7 to 10 days after the procedure. Most patients can resume customary activity in two weeks. In addition to utilizing cryoablation for the initial treatment of prostate cancer, it is frequently used as curative treatment for individuals who have residual cancer after failure of radiation therapy.
Can any prostate gland with cancer be treated by cryoablation?
Just as with brachytherapy, there are size limitations above which prostate cryoablation cannot be effectively delivered. This is generally around 40 cc. Larger glands can often be reduced to effective size range by pretreatment with LH-RH agents such as Lupron. Additionally, there should be a reasonable expectation that the cancer has not spread to pelvic lymph nodes or distant organs.
How is the rectum protected from freeze damage?
The extent of the freeze process is monitored visually with ultrasound and electronically with thermocouples. Saline is sometimes injected into the tissues between the rectum and prostate to further separate the structures.
Are there age limitations for treatment by cryoablation?
No. Any patient with prostate cancer who can tolerate 90 minutes of general anesthesia can be considered for cryoablation. However, younger men would be strongly encouraged to consider surgical removal of the prostate gland as an alternative to either cryoablation or to radiation therapy.
If I have cryoablation and sometime later cancer is again found in my prostate can it be treated?
Yes. There are multiple options for retreatment if the cancer is still within the confines of the prostate gland. Cryoablation can be repeated any number of times since, unlike radiation, the effect of freezing is not cumulative. Radiation therapy by seeds or external beam can also be given after cryoablation. Surgical removal of the prostate gland is rarely considered after either cryoablation or radiation therapy.
Can nerve sparing for potency preservation be done with cryoablation?
Yes, but that is still considered experimental. Selective treatment of certain areas of the prostate is not the accepted standard for treatment of prostate cancer, since cancer of the prostate is considered to be a multifocal process. In general the entire gland must be treated for the best chance of a cure. To intentionally spare the area of the gland immediately adjacent to the recognized path of the nerve which mediates sexual function risks leaving some cancer untreated.
Do I need to be prepared for a blood transfusion to have cryoablation?
No. There is almost no blood loss with the cryoablation procedure. There may be some bruising of the perineal and scrotal skin, and rarely a small amount of blood in the urine after the procedure, but blood loss is negligible and transfusion is not a consideration.
Will I need a catheter after the cryoablation procedure?
Yes. A suprapubic catheter will be placed during the operative procedure. A urethral catheter will not be needed. You will need to keep the suprapubic catheter on drainage to a bag for several days, and then begin clamping it off. When swelling in the treated gland subsides sufficiently to allow you to urinate through the urethra, the suprapubic tube will be removed. This is done on your return visit to the office, usually about one week after the procedure.
How long should I expect to be disabled after cryoablation?
Most men can return to a full activity status after the suprapubic tube is removed. If the tube is required for a somewhat longer period, that may delay return to full activity. Some men have scrotal edema (swelling) that makes strenuous activity uncomfortable. This occurs from temporary blockage of lymphatic channels by the freezing process. There are no incisions that require prolonged activity restrictions to allow healing.
How often does impotency occur after cryoablation?
Frequently. If preservation of potency is a major concern, then an alternative therapy should be considered. Monotherapy by radiation (seeds OR external beam) generally has a lower rate of impotency. Radical prostatectomy with nerve sparing technique also has a lower risk of impotency. Nerve sparing with cryoablation can be done, but is considered experimental at this time.
What is the chance of incontinence of urine after cryoablation?
True incontinence rarely occurs with cryoablation. Stress incontinence can occur if the prostate apex contains cancer and must undergo aggressive treatment to assure complete eradication of the cancer.
Will I need help at home after cryoablation?
Generally yes, but not skilled nursing assistance. How much help you may need is very dependent on your level of functioning before the procedure. You may need some assistance the first few days since this is outpatient surgery and you will need to take a number of oral medications on schedule, as well as manage your urine drainage bag. You should not have a lot of pain or discomfort, and will be able to ambulate before you leave the hospital on the day of your procedure.
How will I know that the treatment has been successful?
As with any other prostate cancer treatment option, the postoperative PSA blood test will be the primary indicator of a successful treatment. We will obtain a PSA level three months after the procedure, and then every six months for five years. After five years PSA monitoring is generally done annually. We expect to see the PSA come down to a level well below 0.5 ng/dl and remain at the lowest level achieved. Three successive rises in the PSA after reaching the lowest point would raise concern about residual or recurrent prostate cancer.