Study Shows Removal of Additional Lymph Nodes May Be Unnecessary

For many women with early-stage breast cancer, removing more than just the sentinel lymph nodes may be unnecessary -- even if cancer cells are found.

Breast cancer patients whose cancer has spread to the sentinel lymph nodes live just as long regardless of whether additional underarm (axillary) lymph nodes are removed, researchers report.

If cancer cells spread from a breast tumor, the sentinel nodes are normally the first place they go. Doctors can find the sentinel nodes and remove them with a small surgical procedure. If no cancer is found, removal of the remaining lymph nodes is not necessary.

When cancer is detected in the sentinel lymph nodes, American Society of Clinical Oncology (ASCO) guidelines, which most doctors follow, call for surgical removal of more lymph nodes under the arm to look for additional cancer cells. The procedure is called axillary node breast dissection.

"Our findings suggest that there may not be a benefit to removing more lymph nodes, and that women can avoid the risk of additional side effects that come with more extensive lymph node removal," says study head Armando E. Giuliano, MD, director of the John Wayne Cancer Institute Breast Center in Santa Monica, Calif.

Those side effects include pain, lost sensation, discomfort, and swelling (lymphedema) of the affected arm that can last for years, even decades.

Giuliano presented results of what he called the largest late-stage phase III study of axillary node dissection for sentinel node-positive women to date at ASCO's annual meeting.

No Benefit to Additional Surgery

The study involved 991 women who had lumpectomy, radiation therapy, and positive sentinel nodes. They were randomly assigned to have no more nodes removed or to have 10 more nodes removed.

By five years later, women who didn't have any more nodes removed were doing just as well on every measure:

    * 92.5% were alive vs. 91.9% who got additional surgery.
    * 83.8% were free of cancer vs. 82.2% of the additional-surgery group.

All of the differences could have been due to chance, the researchers say.

Lymph Node Removal: One Size Does Not Fit All

Some doctors are already moving away from performing axillary lymph node surgery in older women and those with the tiniest cancerous growths in the nodes, says Thomas B. Julian, MD, of Allegheny General Hospital in Pittsburgh.

That's because modern drug and radiation treatments given to women after breast-conserving therapy are likely to kill off any cancer cells in the lymph nodes anyway, he says.

"These data give us a little more confidence that we don't have to remove [the axillary lymph nodes] in these women," Julian tells WebMD.

But for women with larger nodal growths -- and that's still pretty tiny, anywhere from 0.2 millimeters to 2 centimeters, or from ten-thousandth of an inch to about a tenth of an inch -- node removal is still standard and will probably remain so, Julian say.

"I don't think the word is in. We need more data," he says.

"For women with smaller metastases, a lot will come down to patient preference," Julian says.

About 25% of women who undergo breast-conserving surgery for early-stage breast cancer have positive sentinel lymph nodes, according to Julian.

 

Study Underpowered

One problem with the study is that the researchers only managed to enroll 800 of the 1,900 women originally intended.

Giuliano says it was "unlikely" the additional patients would have changed the findings, and several doctors asked by WebMD agree.  It does make it "harder to extrapolate the results," Julian says.

Julian's own research, also presented at the meeting, confirm that for women whose sentinel nodes are cancer-free, removing more lymph nodes from the underarm area is unnecessary.

This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.

 

 

Charlene Laino - WebMD