Breast cancer surgery began long before radiation therapy, chemotherapy or hormonal therapy existed. At that time surgery was the only available treatment. The standard of care was radical mastectomy – removal of the entire breast tissue with the underlying muscle and removal of all the lymph nodes from the arm pit. The surgery is terribly disfiguring and debilitating, but was the only thing standing between patients and a fatal illness. Radical mastectomy was first performed in the 1880s and remained the standard of care until the 1970s when it was replaced by lumpectomy.

Lumpectomy involves removing only the malignant tumor with some healthy tissue around it and sparing the remaining breast. It was found to be as effective as radical mastectomy but was still performed with the removal of lymph nodes from the arm pit.

For many women the consequences of the arm pit surgery are worse than those of the breast surgery. The lymph node removal can lead to discomfort and swelling in the arm and can predispose to infections. Nevertheless this surgery remained the standard of care as it was thought to be essential to stopping any microscopic cancer that had spread from the breast into the lymph nodes.

The next leap forward in minimizing the harm of surgery for breast cancer patients came in the 1990s. A technique called sentinel lymph node biopsy pioneered by Dr. Armando Giuliano allowed surgeons to identify the first lymph node that cancer cells are likely to reach when leaving the breast. The surgeon can then just remove that node (or two or three) and leave the rest. It was shown that if these sentinel nodes are free of cancer cells, the rest of the nodes in the underarm will also be cancer-free. This resulted in many women being spared removal of the lymph nodes.

This week, a new study will make many women’s breast cancer surgery even less invasive. A team led by Dr. Giuliano performed a study to test whether taking out all the underarm lymph nodes is helpful. The study was published in the Journal of the American Medical Association. The study randomized women with early stage breast cancer with positive (malignant) sentinel nodes. One group underwent surgery to remove all the lymph nodes from the underarm, the other group did not. All women underwent lumpectomy and radiation. Some women in both groups also had chemotherapy or hormonal therapy.

Both groups did equally well from their cancer with over 90% survival over 5 years. The women randomized to surgery, however, had many more complications related to arm pain, swelling and infections. So for women who match the specific criteria of the study, removal of all the lymph nodes is no longer necessary.

Learn more:

New York Times article: Lymph Node Study Shakes Pillar of Breast Cancer Care

New York Times Q. and A.: Breast Cancer and Lymph Nodes

Journal of the American Medical Association study: Axillary Dissection vs No Axillary Dissection in Women With Invasive Breast Cancer and Sentinel Node Metastasis