TUESDAY, Nov. 29, 2005 (HealthDay News) -- Long-term research has found that laser surgery using magnetic resonance guidance is effective in treating cancerous liver tumors in some patients, German researchers report.
In this 12-year study, 839 patients at the University of Frankfurt received magnetic-resonance-guided, laser-induced thermotherapy for the treatment of liver tumors resulting from colorectal cancer. Under the procedure, laser light is used to destroy tumor tissue.
The report was to be presented Tuesday at the Radiological Society of North America's annual meeting, in Chicago.
In the trial, lead researcher Dr. Martin Mack, an associate professor in the university's department of diagnostic and interventional radiology, and colleagues treated 2,506 liver tumors and tracked patient survival to evaluate the long-term results of the procedure.
Using the laser technology, the average survival rate from the date of diagnosis was 3.8 years, which compared well with survival rates after traditional surgery, which are usually 1.5 to 5.0 years, the researchers reported.
According to Mack, laser ablation has many advantages over other treatments.
"Traditional surgical resection has higher morbidity and mortality rates than laser ablation," Mack said in a prepared statement. "Laser treatment can be done on an outpatient basis under local anesthesia. Typically, the patient stays only a couple of hours, instead of a couple of weeks in the hospital after surgical liver resection [surgery]," he added.
In addition, laser surgery can be used to treat tumors in both halves of the liver -- often during the same procedure. This is practically impossible in a traditional surgery where only the left or right lobe is surgically excised, the researchers note.
Moreover, if new tumors are found during follow-up exams, it is easier to do another laser treatment than to subject the patient to another invasive surgery.
"Many surgeons are already performing local ablation instead of resection, because they have already recognized the positive effect of local ablation," Mack said. "I believe that minimally invasive tumor ablation together with chemotherapy will play the most important role in the treatment of tumors in the years to come."
One expert, however, doesn't think this method is as good as standard surgery for the treatment of liver cancer.
"I would be wary of making too much out of this new technology," said Dr. Charles Cha, an assistant professor of gastrointestinal surgery and surgical oncology at Yale University School of Medicine.
"The long-term survival presented by Mack's group is impressive and does demonstrate some promise for this new and experimental technology," Cha added.
But, he noted, "the five-year survival after resection for metastatic colon cancer is around 40 percent, much higher than the 24 percent reported. In addition, there was no surgical arm to compare to, and the conclusion that this technology is better than resection is a bit of a stretch."
The results with either cold (cryotherapy) or heat (radiofrequency ablation) for the treatment of metastatic colorectal cancer have not yet matched the results of surgery, which remains the gold standard, Cha said.
"Until more definitive evidence is available, patients should not consider this technology as a replacement for standard surgical therapy, but rather as an alternative if surgery is not possible," he said.
Another expert agreed.
"This is the only group that has really done this procedure," said Dr. Ronald W. Busuttil, chief of the division of liver and pancreas transplant at the University of California, Los Angeles School of Medicine. "It has not been duplicated."
Busuttil said he thought that there are a lot of other methods that can be used to treat liver tumors caused by colorectal cancer that do not include surgery.
"For this technique to really come to the fore, it needs to be compared against surgery and radiofrequency ablation," he said.
"It's interesting," Busuttil said, "but I don't know if it's ready for prime time."
More information
The National Cancer Institute can tell you more about liver cancer.
