Axillary Radiation as Effective as Surgery in Some Breast Cancers

Among women with early breast cancer, those with cancer spread to their sentinel axillary lymph node that is not palpable, appear to achieve equivalent survival with less lymphedema when treated with axillary radiation instead of surgery to remove axillary lymph nodes. These results were recently presented as a late-breaking abstract at the 2013 annual meeting of the American Society of Clinical Oncology.

Early breast cancer refers to cancer that has not spread from the breast to distant sites in the body. However, cancer cells sometimes spread to the nearest axillary (under the arm) lymph node. The lymph node that receives the initial drainage from the area of the cancer is referred to as the sentinel lymph node. Patients who have spread to the sentinel axillary lymph node (or several axillary lymph nodes) have what is referred to as node-positive early breast cancer.

Standard therapy for patients who have early, node-positive breast cancer has typically consisted of extensive removal of the axillary lymph nodes. Unfortunately, this often left patients with chronic side effects, such as lymphedema and disfigurement.

Lymphedema is swelling, numbness, pain and a reduction of range of motion of the entire shoulder and arm on the side of the body that the lymph nodes were removed. Lymphedema is often a lifelong issue and reduces the quality of life of patients.

Recently researchers have been evaluating the effects of radiation to the axillary area instead of surgical removal of axillary lymph nodes in node-positive breast cancer. At this year’s ASCO, researchers from the Netherlands Cancer Institute in Amsterdam reported the latest results from the AMAROS trial. This trial included 1,425 women with early stage, node-positive breast cancer. The cancer spread to axillary lymph nodes was nonpalpable (could not be felt upon physical examination), but was found through standard laboratory tests. The cancer in the breast could measure up to 5 cm.

One group of patients was treated with radiation to the axillary area and the other group was treated with the surgical removal of the axillary lymph nodes.

At 5 years, survival was 93% for all patients.
At 5 years, recurrence rates were 0.5% among those with surgical removal of the lymph nodes and 1.0% among those treated with radiation.
Lymphedema was significantly reduced in the group of patients treated with radiation, compared to those who underwent surgery to remove the lymph nodes.
The researchers concluded that among women with early, node-positive breast cancer, it appears that radiation to the axillary area appears just as effective in terms of survival as compared to the surgical removal of the axillary lymph nodes. Importantly, radiation was associated with a significant reduction in lymphedema compared to surgery. However, the authors caution that this group of women had non-palpable axillary lymph nodes and had early cancer spread, so this treatment choice may not be appropriate for all early breast cancer patients.

Women with early breast cancer should speak with their physician regarding their individual risks and benefits of all their treatment options.

Reference: Rutgers E, et al. Radiotherapy or surgery of the axilla after a positive sentinel node in breast cancer patients: final analysis of the EORTC AMAROS trial. Proceedings from the 2013 annual meeting of the American Society of Clinical Oncology. Late-breaking abstract LBA 1001.