Women might be spared unnecessary and debilitating additional surgery during breast cancer treatment because of a technique developed in part by a local surgeon.

Results from early studies were reported by surgeon David Krag in the lead article in today's New England Journal of Medicine. Krag is a professor at the University of Vermont and chief of surgical oncology at Fletcher Allen Health Care.

If the technique continues to be successful and becomes routine, it could be a major step in caring for women with breast cancer, says Dr. Patti O'Brien, a Burlington doctor who was diagnosed with breast cancer in 1996.

O'Brien, 45, suffered one of the most common side effects of having lymph nodes removed during breast cancer surgery her arm swelled with fluid, making it painful and almost impossible to move, an affliction called lymphedema. Some women can never wear normal clothes, and all women with the problem are susceptible to potentially serious infections.

"I will never get full use of my arm back" because of the lymphedema, she said.

Not having to have lymph nodes removed is "like night and day," in terms of recovering from the surgery. O'Brien speaks from experience; although she had a double mastectomy, only one set of lymph nodes was removed.

A woman has a 1-in-8 risk of contracting breast cancer in her lifetime; in Vermont, 330 women were diagnosed with breast cancer in 1997, according to the American Cancer Society.

Cancer spreads from the breast through the lymph system, the system that carries infection-fighting fluid throughout the body. In the course of normal breast cancer surgery, doctors routinely remove all the lymph nodes under a woman's arm and breast to see if the cancer has spread. Once the lymph nodes are removed, fluid can accumulate in the arm, causing lymphedema.

Krag's technique takes advantage of the fact that some lymph nodes, called sentinel nodes, are the first to intercept the body's fluids. By injecting a radioactive substance into the lymph system of the breast, surgeons can use the medical equivalent of a Geiger counter to identify the sentinel nodes, and test only those nodes for cancer. If those nodes have cancer, then all the nodes should be removed.

If the sentinel nodes are cancer-free, it's highly likely the cancer hasn't spread, Krag hypothesizes, and the patient can be spared surgery. In general, 75 percent of all breast cancer patients have lymph nodes that are free of cancer, but until Krag's technique, there was no other way than surgery to find that out.

"It's like throwing a stick in a stream to see where it goes," Krag says of injecting the radioactive substance as a tracer. "Then we can go after that limited set of lymph nodes."

The substance, technetium-99, is no longer radioactive after six hours. It is not harmful as used in the test, Krag said.

One other advantage of Krag's technique is that in about 8 percent of patients, the sentinel nodes are not in the armpit at all, which means the traditional technique of removing the nodes under the arm might miss some cancer spread.

For Polly Connell, a 48-year-old Underhill Center woman who participated in Krag's study, the research was a way to help other patients in the future. Because of the study design, Connell, like all study participants, was first tested with the radioactive tracer to find sentinel nodes. Later the same day, doctors removed all her lymph nodes to see if the technique had correctly detected cancer spread.

"I knew from the outset that this study wouldn't make any difference for me," she said. "Regardless of the results, they were still going to remove my lymph nodes. But I thought it could mean for other women, they wouldn't have to go in and take more lymph nodes, and it would be easier to heal."

The results reported today indicated that of 405 patients in whom doctors could identify sentinel nodes, the technique identified whether cancer had spread in 397 of them. But in 13 of the 114 women whose cancer had spread, the technique failed to identify the spread, a false negative rate of 11 percent. That is higher than acceptable, Krag said. A $1.5 million grant from the National Cancer Institute will fund the next series of trials to help modify the technique.