Surgeons at Thomas Jefferson University Hospital are using a new technique
to essentially "melt" away cancerous liver tumors. The technique, called
Radiofrequency Interstitial Tumor Ablation, or RITA, promises faster, more
specific treatment with fewer side effects and shorter hospital stays than with
RITA delivers electrical energy through a special catheter to the tumor. The heated cancer cells die within 15 minutes. Though surgeons prefer the standard method of cutting out the tumor, approximately 80 percent of liver tumors cannot be surgically removed at diagnosis. Other options include chemotherapy, which has limited effectiveness, and cryosurgery, which entails freezing tumors.
Cryosurgery is generally an effective treatment, but requires patients to remain hospitalized for several days. "RITA gives us a huge advantage over cryoablation," says Ernest Rosato, M.D., assistant professor of surgery at Jefferson Medical College. "While patient results have been good using cryosurgery, it requires a hospital stay of four or five days and has some side effects." Cryosurgery involves freezing tumor cells to reduce tumor size, he explains. While cryosurgery may work well, the probes used are awkward and procedures require more invasive surgery than does RITA.
With RITA, Dr. Rosato says, "We can do what we do with cryosurgery but with fewer side effects. Patients can even have this treatment while they are also receiving chemotherapy. It's a minimally invasive way of dealing with tumors."
In the RITA system, a catheter is attached to four prongs that encompass and deliver electrical energy to the tumor. Surgery is performed laparoscopically, through tiny incisions and with the use of small lighted cameras at the end of long tubes. As tissue temperatures rise above 113 degrees Fahrenheit, cell protein is permanently damaged, killing the cell.
The liver is a frequent site to which cancer spreads, particularly from the colon. Cancer is most dangerous when it goes to other areas in the body. "Many patients that come to us are almost hopeless candidates," says Francis Rosato, M.D., professor and chair of surgery at Jefferson Medical College. "Patients have failed chemotherapy and are looking to have their tumors treated," he says. "We would like to see them earlier, after chemotherapy, rather than waiting until they get into late stages of disease."
He calls RITA "revolutionary in terms of minimizing patient risk, loss of ability to work, and expense." Doctors using RITA need to know the exact location, size, shape and orientation of a cancerous tumor. Therapy can be applied to a range of different sized tumors. "In a larger tumor," he explains, "doctors can start in one area and try to wipe the tumor out. We might take four or five passes with RITA, see what tumor remains to be treated, and re-treat."
He is amazed at how well patients have done to date. "What's striking is that every patient we've treated wakes up and asks if they can go home. It is extraordinary how patients are tolerating this treatment." Some patients can be treated with RITA under conscious sedation. Most patients are seen as outpatients. "We're treating some patients that we couldn't have treated in the past, such as those with esophageal cancer that has spread to the liver." says Dr. Ernest Rosato. "We can treat primary liver cancers--cancers that begin in the liver, and metastatic colorectal tumors to the liver as well as some metastatic melanomas. "It seems like a reasonable approach for tumors that don't warrant the stress of a full-blown operation," he says. "We see four times as many patients with metastatic disease as those we see with primary liver cancer. Gastroenterologists may see many more hepatitis patients who have primary liver cancer, however."
For any cancer treatment, the bottom line regarding effectiveness is whether or not patients not only live longer, but also better, healthier lives. For now, no one knows the long-term impact of the RITA treatment on patients' health. "We don't know what the ultimate results will be," Dr. Ernest Rosato says. "It will take us several more years to document the efficacy of this program."
The instrumentation, which is approved by the federal Food and Drug Administration, is developed by RITA Medical Systems, Inc., of Mountain View, Calif.
For physician referral information call 1-800-JEFF-NOW.
Revised:December 23, 2004. URL: http://www.kcc.tju.edu/news/RITA.htm