Heat therapy said to hold promise in breast cancer

Therapy that "cooks" small tumors could soon provide an alternative to surgery for women in the early stages of breast cancer, according to one researcher.

The tactic, known as thermal ablation, is still considered experimental as far as breast cancer is concerned, but it is more commonly used against certain other medical conditions, including liver cancer.

To perform thermal ablation, doctors use non-invasive ultrasound or magnetic resonance imaging (MRI) to define the borders of a small tumor.

From there, a needle inserted into the tumor delivers heat - produced either by radiofrequency energy or a laser - that destroys the cancerous tissue. In some cases, doctors may instead kill the tumor by freezing it with liquid nitrogen.

A limit to using thermal ablation in breast cancer has been the question of whether imaging techniques can accurately define the borders of a tumor to ensure that the heat therapy kills all of the cancerous cells. New, high-resolution MRI is addressing that concern, according to Dr. Steven E. Harms, director of imaging research at the University of Arkansas for Medical Sciences in Little Rock.

Harms spoke about thermal ablation Thursday at a news briefing held by the Radiological Society of North America.

In an interview with Reuters Health, he said that high-quality imaging will be "key" in bringing thermal ablation into widespread use for early breast cancer.

"We're getting very high-quality imaging now," said Harms, who is also medical director of Aurora Imaging Technology Inc., maker of an MRI system designed specifically to image breast tissue.

Harms and his colleagues have performed more than 50 MRI-guided thermal ablations on women with breast cancer. The women also underwent surgery afterward to ensure that the imaging correctly sized up the margins of the tumor, and that all of the cancerous tissue, plus a small area of surrounding tissue, was destroyed.

In addition, Harms said he has performed thermal ablation alone on three women with small breast tumors. After four years of follow-up, he said, none has had a recurrence. He and his colleagues plan to conduct a clinical trial using thermal ablation without additional surgery in women with small, solitary breast tumors.

According to Harms, since thermal ablation is minimally invasive it produces much less scarring than lumpectomy, the surgical removal of a breast tumor. "The cosmetic result is probably the biggest advantage," he said.

The researcher also said he suspects thermal ablation will turn out to be as effective as lumpectomy for the appropriate patients. "But," he added, "we need to prove that in clinical trials."