The mere mention of doctors freezing patients so they can be preserved for decades until cures are found conjures up memories of some absurd movie thrillers. But freezing, or cryotherapy, is not entirely far-fetched or the stuff of science fiction.
Just last month, a Chicago surgeon used cryotherapy to freeze, and thereby destroy, two malignant tumors in a woman's breast. It was the first time cryotherapy has been used to treat breast cancer in a human being. The patient, who was administered a local anesthetic during surgery, was able to check out of the hospital a few hours after the operation, and required no medication for pain.
Her doctors are optimistic that the frozen tumors will not return. "Of course using cryosurgery to treat breast cancer is still very much in the investigative stage," cautions Dr. Edgar Staren, surgical oncologist at Rush Presbyterian St. Luke's Medical Center in Chicago, who performed the 90-minute operation. "But I'm very enthusiastic about the ease of the procedure and its immense possibilities." Staren plans to freeze the tumors of three more breast cancer patients in coming weeks.
For decades, freezing has been an accepted method for obliterating unwanted cell growth on the skin, eyes, cervix, and other easy-to-reach parts of the body. Cryotherapy was used during the 1950s to rid patients of deep internal cancers as well.
MISFIRES. But cryotherapy equipment was primitive back then. "There were a lot of complications because the devices they used for visualization and freezing were not very accurate," says Dr. Andrew Von Eschenbach, chairman of the department of urology and a cryosurgeon at the University of Texas M.D. Anderson Cancer Center in Houston. "They ended up freezing more than just the tumor, which led to complications." As a result, cryotherapy was pushed aside in favor of more tractable cancer-killing strategies, such as chemicals and radiation, which were less likely to damage surrounding tissues.
Now, thanks to advances over the last ten years in ultrasound imaging technology, cryosurgery is making a comeback. For one thing, surgeons no longer have to cut a patient open to get a look at isolated parts of the body. Moreover, in 1989, Jeffrey K. Cohen, director of urology at Allegheny General Hospital in Pittsburgh, teamed with engineers at Cryomedical Sciences in Rockville, Md., to develop a precise freezing mechanism called the AccuProbe. The apparatus delivers liquid nitrogen at temperatures approaching minus 185 degrees Celsius, through probes the size of a fountain pen. AccuProbe has emerged as the leading surgical freezing device in U.S. hospitals: Some 120 are in use.
Cohen began performing cryosurgery in 1990 on men with prostate cancer who had failed all other forms of treatment, save for having their prostates surgically removed. The procedure, he says, has been so effective in eradicating patients' tumors without damaging surrounding tissue that he started performing cryosurgery on prostate cancer patients "right off the bat." Cohen reports that of the 118 prostate patients who underwent cryosurgery as their first and only form of treatment, 83% have no lingering evidence mf the disease.
While cryosurgery is still most often used to combat prostate cancer, the therapy is being tried increasingly on other types of cancer. Doctors have performed cryosurgery on hundreds of liver and kidney cancer patients with promising results. Dr. Robert Kane, a radiologist who performs cryosurgery on liver cancer patients at Deaconess Hospital in Boston, says the procedure "is less of an insult to the body than other cancer therapies, requires less recovery time in the hospital, and it kills the cancer."
Yet even in cases of prostate cancer, cryosurgery's experimental designation makes it a last-resort treatment when all other therapeutic options have been exhausted. Insurance companies aren't convinced yet, either. To date, insurance coverage has been spotty and handled on a case- by-case basis.
Still, proponents of surgical freezing insist the treatment will soon become a frontline defense in the fight against cancer. Says Cohen: "Cryotherapy is so effective that I think you are really going to see it take off in the next couple of years, as a preferred, first-choice cancer treatment." It might even make a nice movie with a happy ending.