TUESDAY, March 30, 2004 (HealthDayNews) -- A technique that uses heat to "cook" tumors was found safe in treating small, invasive breast cancers, a new study found.
"It is experimental, and it is preliminary. I don't want to raise false hopes," says Dr. Bruno Fornage, a professor of radiology and surgical oncology at the University of Texas M.D. Anderson Cancer Center in Houston. He is lead author of the study, which appears in the April issue of Radiology.
But he and other experts add the new approach looks promising.
Called radiofrequency ablation, the technique has been dubbed "cooking tumors with needles." Ultrasound imaging is used to guide a needle-electrode to the center of the tumor, and then a temperature of about 200 degrees Fahrenheit (or 95 degrees Celsius) is applied for about 15 minutes to destroy the cancerous tissue.
"It basically coagulates the tumor," Fornage says.
The technique is used already, Fornage says, for non-operable liver tumors and has been studied to treat lung, bone, brain, kidney and prostate tumors.
Fornage and his colleagues used the ablation technique to treat 21 breast cancers in 20 patients. All were 2 centimeters or less in diameter -- about the size of a grape.
The study was a feasibility study, Fornage says, and all the women underwent the procedure immediately before their scheduled lumpectomy or mastectomy. "We did radiofrequency ablation and then removed the specimen right away because the patient was scheduled for surgery," he says.
A pathologist then examined the tissue, "and that's what confirmed that the tumors had been completely destroyed," Fornage says.
In all 21 cases, the target tumor that was seen on the ultrasound was completely ablated, Fornage says. However, one patient whose tumor had first been shrunk by chemotherapy had residual cancer found around the ablated target.
"We decided then that we should never apply this procedure to patients who had been downstaged," says Fornage, referring to women whose tumors shrink after chemotherapy and the cancer is then downgraded to a less serious stage.
As promising as the technique looks, Fornage says one big limitation is there's no way to be sure the technique destroyed all the cancer. During surgery, he says, "you remove the tumor and the pathologist examines the margins. If there is some tumor left, the surgeon goes back and takes more tissue out."
With the ablation technique, however, no tissue is removed and there is currently no way to determine if it got all the cancer.
Another cancer expert, Dr. Ellen Mendelson, chief of breast imaging and a professor of radiology at Feinberg School of Medicine at Northwestern University, also sees that as a limitation. The main problem with the procedure, which she calls promising, "is the problem of margins -- how we can assure that the entire cancerous area has been removed."
The solution, say Mendelson and Fornage, may be to use imaging such as magnetic resonance MRI or PET scans, something that could detect cancer before mammograms are capable of doing so.
Even with the limitations, says Mendelson, "Dr. Fornage's study is a trailblazer."
And it follows what she sees as a trend in radiology and medicine that looks for less costly, less invasive techniques with less recovery time. "We're trying to accomplish the most with the least," she says.<. p="">
"This is an experimental study which I would say paves the way for other studies that will be needed," Fornage says. "Right now we have shown [radiofrequency ablation] is feasible and it is safe. But we still need to show that it is at least as good as the standard treatment."