A surgical procedure that literally freezes cancer in its tracks is giving hope to patients who have not been helped by traditional therapy.
Cryosurgery, already in use for prostate cancer, has only recently been used to treat liver tumors. Emory University Hospital is one of the few medical centers in the country offering the treatment, which is seen as the only viable option for many patients whose cancers have spread to their livers. This fall Emory Hospital will be one of the sites for an Eastern Cooperative Oncology Group (ECOG) study of the long term survival of patients and recurrence rate of tumors following cryosurgery for liver tumors.
Elizabeth Morris, a 76-year-old Carrollton, Ga., resident, underwent a year of chemotherapy after four tumors were discovered in her liver. When the chemotherapy did not destroy the tumors, Morris was referred to Emory surgical oncologist Charles Staley.
"Because Mrs. Morris had multiple unresectable tumors, and because chemotherapy failed to help her, we felt that cryosurgery was a good treatment option," Staley said. "When patients have multiple tumors on both sides of the liver, 70 percent of the time traditional surgery will not help them. There simply would not be enough liver tissue left to function adequately. Cryosurgery involves much less removal of the normal liver than traditional surgery."
Resection, or surgical removal, is the traditional treatment for tumors in the liver. However resection may not be an option for patients who have damaged livers or multiple metastatic tumors. Staley says of the more than 30,000 people each year who are diagnosed with cancer which has spread to the liver, only a few thousand can be helped with traditional resection surgery.
Those 25,000 who do not qualify for resection can be treated with intravenous chemotherapy, but only 15 percent can expect that treatment to help. Previously, for the patients who did not respond to chemotherapy, like Elizabeth Morris, there were no further proven treatment options. Patients receiving no therapy usually do not survive more than three years after diagnosis.
The technology of cryosurgery has been around since the 1960s, and has been used to treat skin cancers and prostate cancer. It involves "freezing" tumors by putting liquid nitrogen on the affected area. It has not been applicable to the liver because there was no reliable way to monitor the exact placement of the instruments that deliver the liquid nitrogen.
A 1986 study showed that intraoperative ultrasound, or ultrasound done in the operating room, could be used to identify the number and position of the tumors as well as to track the freezing process. Follow-up studies of cryosurgery in animals and humans showed great promise, and it has recently begun to be used as a standard treatment for advanced liver cancer. The liquid nitrogen is delivered by a probe directly into the tumor and the surrounding area. The tumor then dies and is eventually absorbed into the body. The machine used to perform the cryosurgery at Emory Hospital is the AccuProbe System, manufactured by Cryomedical Sciences Inc.
While a recent episode of the CBS television program "Chicago Hope" portrayed the procedure as a radical new therapy, in reality it is an approved option for patients failing traditional treatment. Patients must meet certain criteria before being considered for the treatment at Emory Hospital. They must be at least 18 years old, have less than five tumors and must have tumors confined to the liver only. An ultrasound must confirm that the tumor or tumors can not be removed by surgery because of their location or because of impaired liver function. The surgeon must believe the cancer is completely removable by cryosurgery or a combination of cryosurgery and surgical resection. "We are not going to put a patient through this procedure unless we can remove all tumor in their livers," Staley said.
For Elizabeth Morris, who recently celebrated her 56th wedding anniversary with her husband James, having the option of cryosurgery came as a blessing.
"I was told that patients with my kind of cancer do not normally live very long. I had the surgery in January of 1996 and I have gone back for two CAT scans after the surgery, and they haven't found any more cancer," Morris said. "I have always been healthy, but I never really appreciated what a blessing good health is. I'm feeling wonderful now."