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Doctors experimenting with new technique to find lymph-node malignancies

Ever since doctors first started removing tumors, surgery for breast cancer has been a complicated, painful procedure that often involves cutting around muscle and major arteries.

To check for the disease, doctors routinely remove dozens of lymph nodes near a woman's armpit. Then they examine a select few to check if the cancer has moved beyond the breast. But in ongoing tests at East Carolina University, doctors are experimenting with a new technique - one that might eventually simplify this process, improving a doctor's ability to detect cancerous cells while speeding a patient's recovery.With the new procedure, doctors use a combination of dyes and radioactive tracers to identify a single lymph node - the "sentinel node" - that is most likely to contain cancer cells. Then they subject this node to a battery of tests to judge the cancer's possible spread.

By doing so, researchers hope to replace a painful, often disabling, operation with a simple incision and a series of stitches. "It's going to be tremendous for women with breast cancer," said Dr. Lorraine Tafra, a cancer surgeon who is trying to perfect the technique at ECU's School of Medicine.

The ECU tests are part of an effort by doctors to be more "surgical" in their surgical techniques. In this case, the tests involve breast cancer, a disease that kills about 44,000 women nationwide each year and one that critics say has been slighted by the U.S. medical establishment. The technique still faces some obstacles. What if, for example, the cancer has somehow sneaked past the sentinel node and goes undetected by doctors? To make sure the technique is reliable, Tafra and other surgeons are comparing the two approaches at medical centers in Texas, Florida and California.

On a recent morning in Pitt County Memorial Hospital in Greenville, doctors tested the technique on a cancer patient who agreed to give up her "sentinel node." During the procedure, a surgeon pulled a small piece of tissue from an incision in the patient's armpit and pressed it to the tip of a wand-like probe.

"Well, we've got the hot node out," he said to Tafra, who stood nearby monitoring the probe's meter as it went "whoop, whoop, whoop." Rather than temperature, it was radioactivity that was making the breast cancer patient's lymph node "hot." Tafra and her team had injected the tissue surrounding the woman's tumor with a radioactive tracer and a blue dye. The tracer and dye, they believe, will follow the same route as a tumor's cancer cells when it drains into the lymph nodes. So, the node most likely to hold the killer cells also sets off the meter.

Tafra then sent the chilled node up to a hospital lab, where technicians subjected it to a series of elaborate tests.

Since this approach is unproven, Tafra's partner, Donald Lannin, went on to remove a cluster of nodes from the woman lying on the operating table. Tafra hopes that, at the very least, the two techniques will be equally accurate in determining the cancer's spread. But it's possible, she said, that it will be far more accurate.

"They can subject this node to a more rigorous testing than they can for 30 nodes," Tafra said. "If you hand them one node, they can have a field day with it." The standard node analysis finds about one cancer cell in about 10,000 normal cells. By analyzing cross-sections of a single cell in more detail, doctors can find one cancer cell in 100,000, Tafra said.

With most cancers, the lymph nodes are the first place doctors examine when they look for trouble. These immune system glands are strung like Christmas lights along the vessels of the body's lymphatic system. In a healthy body, this web-like network drains fluid from tissues and ferries healing immune cells to wherever they are needed. In a cancer patient, it can also carry deadly tumor cells to healthy tissue and organs.

During most breast cancer surgeries, doctors cut around muscle and major arteries and remove a large section of tissue to get to the nodes. Usually, the painful recovery period requires at least one night in the hospital and several days attached to tubes that drain the surgical wound. The new procedure, if successful, would turn all this into a simple outpatient procedure.

Tafra, a 38-year-old who has been working at ECU for two years, learned the sentinel node technique from one of its pioneers, Dr. Donald Morton, director of the John Wayne Cancer Institute in Santa Monica, Calif. Morton designed the procedure for melanoma, an aggressive skin cancer that also spreads through the lymph nodes.

Doctors are now using the technique to find spreading skin cancer they may have missed in the past, said Dr. Douglas Tyler, who is testing the approach at Duke University. "It provides us with a tool to offer patients additional treatment at an early stage," he said.

Not all doctors are upbeat about the experimental approach. Dr. Hilliard Seigler, a skin cancer researcher at Duke, doesn't believe the scientific data is strong enough to conclude that tumors spread through a single node. In some cases, he said, the "sentinel" node can be cancer free when the cancer has actually spread through a different route.

Ultimately, an increase in survival will help doctors determine which approach is best. "That's what you really want to know and that's not clear," said Seigler.

Tafra said she plans to conduct long-range studies to compare survival rates for the two procedures. She is also in the process of recruiting and training doctors at 28 hospitals and surgery centers to test the procedure on about 500 women, which will give her a large enough sample to draw some conclusions.

In the long run, the approach may only be as good as the treatments available to treat cancers that have spread beyond the tumor. Early detection can put doctors in a good position to use chemotherapy and other treatments, said Tafra.

"I'd like to say that as a surgeon, I can cure cancer," she said. "I'm not going to cure cancer, but I can help find it."