A new study, presented at this week s American Society of Clinical Oncology (ASCO) meeting in Chicago, indicates that a finding of a positive sentinel lymph node in the axilla (armpit) of a breast cancer patient may well not require extensive nodal surgery in that axilla. Such surgery, called lymph node dissection. had been thought to reduce the risk of subsequent spread of cancer cells from the local region to invade organs, making cure unlikely. Instead, local radiation to the axilla without surgery was found to markedly reduce one feared complication of surgery, lymphedema (arm swelling) and did not lower the odds of survival.
A prior study, in 2011, had revealed (surprisingly to most breast cancer experts) that finding cancer cells in the uppermost axillary lymph node the sentinel node was not a harbinger of a poor prognosis. From that point, it made sense to evaluate whether removing positive arm nodes would indeed favorably impact spread and survival of breast cancer patients. And so the authors, based in Amsterdam s Netherlands Cancer Institute, studied 1,425 women with small but locally invasive tumors whose lymph nodes were not clinically abnormal (by palpation), but had positive tests for sentinel node cancer cells. Half underwent axillary lymph node dissection (surgery), and they were compared to the control group which had radiation to the axilla, but no surgery (the surgical group also got radiotherapy).
In sum, the outcomes were essentially identical as far as cancer spread and survival were concerned: 93 percent of each group were alive 5 years after diagnosis. Recurrence rates were extremely small, 1.0 percent in the RT group, 0.5 percent in the surgery + RT group. However, lymphedema was reduced dramatically in the RT only group: 22 percent at one year, 14 percent at 5 years about one-half the rate amongst those operated on for lymph node removal.
ACSH s Dr. Gilbert Ross noted, The more experience I have in medicine, the more I have seen the common wisdom turned on its head. When I was in practice, it was obvious, standard of care, to do a lymph node dissection on just about every case of breast cancer. Then came the sentinel node biopsy. Now we have seemingly come to the end of the lymph node dissection era. That is good news for women with locally invasive breast cancer: besides the rigors, physical and mental, of dealing with that disease, the complications of lymphedema often turned out to be the major factor limiting their enjoyment of life. Now far fewer will have to suffer its travails.