Freezing Prostate Cancer Cells to Death
Dec. 3, 2001 -- According to new research, an experimental technique may soon offer men with prostate cancer a more palatable alternative to standard therapies. In cryosurgery, cancer cells are repeatedly frozen and defrosted, until they die -- all without causing the devastating side effects common with existing treatments.
"When men are diagnosed with prostate cancer, often they have to decide between 'watchful waiting' -- doing nothing and hoping the cancer does not grow quickly -- or choosing one of several treatments, all of which ... often cause side effects such as impotence, incontinence, and bowel problems," says study leader Gary M. Onik, MD, in a news release.
The prostate is a walnut-sized gland that surrounds the urethra, just below the bladder. It produces much of the liquid component of semen. Prostate cancer, with 200,000 new cases and 31,500 deaths annually, is the No. 2 most-common form of cancer in men, after skin cancer.
In the two-thirds of men with multiple prostate cancer tumors, any treatment, including cryosurgery, is directed at the entire gland. But in this preliminary study of nine men with only a single prostate cancer tumor, the cryosurgery was focused directly at the tumor itself, leaving surrounding tissue and nerves untouched.
The minimally invasive treatment involves inserting thin, temperature-controlled probes through the skin and into the gland. The cancer cells are then frozen and thawed a few times, causing them to die.
The team, from Florida Hospital Celebration Health's Center for Surgical Advancement, in Celebration, Fla., presented its findings last week at a medical conference in Chicago.
"Although we haven't done the procedure on many patients yet, three-quarters of those we have treated are still potent" an average of three, and as many as six years later, says Onik. He adds that, in contrast, even when a surgeon tries to preserve one erection-controlling nerve while removing the prostate, potency is saved only 20% to 50% of the time.
None of the men in the study experienced a cancer recurrence.
Onik reports another benefit of cryosurgery, when used this way, "is that it is the only procedure that can be repeated without any added complications. If other therapies are used first and fail, often nothing else can be done."