Lymph node axillary radiotherapy (ART) is associated with significantly fewer complications than traditional axillary lymph node removal, and it may be poised to become the standard of care, according to research presented on April 30 at the American Society of Breast Surgeons (ASBrS) meeting in Las Vegas.
"Axillary lymph node dissection is associated with high rates of side effects," said presenter Dr. Mila Donker of the Netherlands Cancer Institute at an ASBrS press conference. "But there have been limited data available on long-term side effects of axillary radiotherapy in patients who are sentinel-node positive. We wanted to demonstrate noninferiority between the two treatments in axillary recurrence rate, as well as compare surgical complications, arm lymphedema, and shoulder function."
Lymph node axillary radiotherapy is an emerging treatment protocol for tumors affecting the lymph nodes, and it appears to have fewer complications than traditional axillary lymph node removal, according to Donker. The study was conducted between 2001 and 2010 by the European Organization for Research and Treatment of Cancer (EORTC) and included 4,806 patients. Of these, 65.1% were sentinel-node negative and 29.7% were sentinel-node positive (744 had axillary lymph node dissection and 681 had axillary radiotherapy).
One year after treatment, 15% of the axillary radiotherapy group, 25% of the axillary lymph node dissection group, and 59% of those who received both therapies had arm lymphedema. At five-year follow-up, arm lymphedema rates were 10% of ART patients, 21% of those treated with ALND, and 58% of the combination therapy group.
Patients' shoulder mobility decreased temporarily for both treatments, particularly during the first year, according to Donker's team. Women treated with more extensive node removal or specialized supraclavicular radiotherapy following surgery experienced greater mobility loss than the ART group.
Overall, the researchers found a 0.43% five-year recurrence rate for axillary lymph node removal and a 1.19% rate for axillary radiotherapy.
"This difference was not statistically significant," Donker said.
Is more evidence needed to show the benefits of radiotherapy compared to surgery? No, according to Donker: Because the study involved nearly 5,000 women from various countries with differing standards of care, it reflects real-world clinical practice, she said.
For patients with positive sentinel nodes, ART is the preferred treatment over ALND given the overall morbidity, and a combination of surgery and radiation increases side effects and should be avoided if possible, she concluded.
The study findings may change surgical guidelines and offer better quality of life for many women, according to Donker -- particularly for younger patients who would otherwise live with the difficult side effects of node surgery, such as lymphedema, for a long time.
"The data strongly support ART as the preferred treatment," she said. "I believe that as a result of this trial, radiotherapy of the nodes will begin to replace surgery."
