Less Axillary Surgery for Breast Cancer: Minimizing Harm
Cancer survival rates are increasing in the US. The American Cancer Society reported recently that by 2022 the number of survivors will soar to almost 18 million, up from 13 million in 2010. In my field, breast cancer, death rates have been decreasing since 1990. A 25% increase in the number of breast cancer survivors between 2010 and 2020 is predicted. These figures mean that those who have been diagnosed with and treated for cancer are living longer, therefore they will have more years during which they may suffer from the unwanted complications and side-effects of their cancer treatment.
There is an increasing awareness about the quality of life of the cancer survivor. The Commission on Cancer has listed as one of its goals for 2012 that each patient be given an individual care plan, detailing, among other things, their plan for survivorship. Emphasis is placed on optimizing function, and complete healing, recognizing that care does not cease when the surgery, chemotherapy and radiation have ended.
As a breast surgeon, I know that lymphedema is a complication dreaded by patients. Lymphedema, swelling of the arm due to disruption of lymphatics, can occur following removal of lymph nodes for staging the disease, and to control recurrence in the axilla. Historically, a full axillary dissection was performed, removing an average of 10-15 nodes from the underarm. The sequela of that surgery was a lymphedema rate of up to 35%. In the late 1990s the technique of sentinel node biopsy was applied to breast cancer. In this elegant procedure, the potential pathway of the metastatic cancer cells is reproduced, leading the surgeon to the nodes that stand sentry (sentinel) to the rest of the axilla.
Usually 2 to 3 nodes are removed, with consequently fewer cases of arm swelling, in the range of 2-5%. The dogma was always however, that if those nodes contained deposits of tumor seen with standard staining methods, then additional nodes had to be sacrificed. A landmark paper published February 2011 in the Journal of the American Medical Association, detailed the results of a trail conducted by the American College of Surgeons Oncology Group (Z0011). Just under 900 patients who had breast conserving surgery (lumpectomy) and no more that two positive nodes found at sentinel node biopsy, were randomized to have either no more surgery or excision of additional nodes. At a median of over 6 years of follow up, there was no significant difference in overall survival or recurrence rates. The authors of the JAMA paper concluded that implementation of this practice change would improve clinical outcomes in thousands of women each year by reducing the complications associated with axillary lymph node dissection and improving quality of life with no diminution of survival.
The publication of the Z0011 data has used a change in surgical management of breast cancer patients across the US. In August 2011, the American Society of Breast Surgeons (ASBrS) issued a position statement on the topic. They emphasized that routine axillary dissection should no longer be required for patients undergoing lumpectomy who met the following criteria: invasive tumors up to 5cm in size; no more than two positive sentinel nodes with no extension of cancer beyond the confines of the node; completion of radiation treatment to the entire breast; and compliance with additional medical treatment.
In December 2011 the International Breast Cancer Surgery Study Group presented their data for a similar trail in which over 900 women were evaluated. Their conclusion aligned with the results of the American College of Surgeons Oncology Group results. The National Cooperative Cancer Network (NCCN) changed the national guidelines for breast cancer treatment for 2012 to reflect the gathering evidence supporting less surgery to the axilla. Surgeons can change. Research presented at the 2012 ASBrS annual meeting showed a change in practice patterns of surgeons at MD Anderson Cancer Center following Z0011 — rates of full axillary dissection have plummeted from 85% to 24%.
CaduceusOur care should be evidence-based, and the evidence is accumulating in favor of less axillary surgery for appropriate patients with breast cancer. And that’s good news for the 226,870 women estimated to be diagnosed with breast cancer in the US in 2012. When I graduated from medical school we pledged a covenant with our future patients. We made a promise — the Hippocratic oath. An oft-quoted part of that oath is primum non nocere — above all do no harm. As surgeons, we harm our patients by making an incision, although the ultimate goal is a good outcome. Perhaps the surgeons’ pledge should also be deinde minui nocere —then minimize harm. Minimize harm by causing fewer complications.
Tags: American Society of Breast Surgeons, breast cancer, cancer survivors, Commission on Cancer, lymphedema, NCCN, primum non nocere, sentinel node biopsy, Z0011