Long-term research has found that laser surgery using magnetic resonance guidance is effective in treating cancerous liver tumors in some patients.
In a 12-year study, 839 patients at the University of Frankfurt received magnetic-resonance-guided, laser-induced thermotherapy to treat liver tumors (metastates) that resulted from colorectal cancer. This procedure uses laser light to destroy tumor tissue.
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 (metastates) and tracked patient survival to evaluate the long-term results of the procedure.
For patients who received the laser technology, the average survival from the date of diagnosis was 3.8 years, which compared well with survival of 1.5 to 5.0 years for those receiving traditional surgery say the researchers.
According to Mack, laser ablation has many advantages over other treatments.
"Traditional surgical resection has higher morbidity and mortality rates than laser ablation," says Mack. "Laser treatment can be done on an outpatient basis under local anesthesia. Typically, the patient stays only a couple of hours in the hospital, instead of a couple of weeks [as is common] after surgical liver resection," he adds.
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 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 it," Mack says.
"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," he adds.
Not Ready For Prime Time?
Some experts, however don't think this method is as good as the standard surgery for the treatment of liver cancer.
"I would be wary of making too much out of this new technology," says 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 concedes, but the five-year survival rate after resection for metastatic colon cancer is relatively good-approximately 40% -and this study did not include a surgical arm to which the laser surgery could be compared.
"The conclusion that this technology is better than resection is a bit of a stretch," he says.
Dr. Ronald W. Busuttil, chief of the division of liver and pancreas transplant at the David Geffen School of Medicine at the University of California at Los Angeles, agrees. "For this technique to really come to the fore, it needs to be compared against surgery and radiofrequency ablation," he says. "It's interesting, but I don't know if it's ready for prime time."
The survival rates of two other types of treatments-cryotherapy and radiofrequency ablation-for metastatic colorectal cancer have not yet matched the results of surgery, which remains the gold standard, Cha says.
"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 says.
Busuttil notes that there are many other ways to treat liver tumors caused by colorectal cancer that do not include surgery.