Axillary Reverse Mapping
One of the pieces of information needed by your doctor, so that he or she can “stage” a breast cancer, is whether or not the cancer has spread to the lymph nodes, or glands, underneath the arm. This area under the arm is referred to as the axilla, and the lymph nodes are known as axillary lymph nodes. This surgery to check the nodes can be either a Sentinel Lymph Node Biopsy (checking a few lymph nodes), or an Axillary Dissection (checking many lymph nodes), depending on your type of cancer. One of the major complications of these procedures is lymphedema, or swelling of the arm. Many surgeons believe that this occurs because of disruption of the drainage channels from the arm that are also present in the under-arm region.
Axillary Reverse Mapping (ARM) is a technique that can help to identify these channels and may be used during your lymph node surgery. During the time of your lymph node surgery, whether it is the sentinel node surgery or axillary dissection surgery, a blue dye is injected in the upper arm. This blue dye helps identify the lymphatic channels and lymph nodes that drain the arm, and the surgeon then tries to avoid disrupting these channels. This technique has been adopted by many breast surgeons with excellent results. Traditionally, the rates of arm swelling after sentinel node biopsy range from 3-8%1 and from 13-40%2 after axillary dissection surgery. The studies that looked at ARM show a lymphedema rate that is lower, around 1-3% for the sentinel node surgery and 4-9%3 for the axillary dissection surgery.
Sometimes, it is not always possible to do ARM, and the surgeon needs to inject the blue dye in the breast to help identify the correct lymph nodes. This may be the case if you have had previous chemotherapy in the breast, or if the lymph nodes are not accurately found with other methods. Additionally, it is possible that the blue lymph nodes and the channels that are identified to drain the arm need to be removed to treat your cancer safely. If this is the case, you may be placed in a special group to watch your arm swelling closely, or even have the option of having these channels reconnected. This is usually done by surgeons well experienced in lymphatic surgery, and may include plastic surgeons also.
It is important to talk your surgeon about your lymph node surgery in detail. Feel free to ask about ARM and if it is right for you.
Ashikaga T, Krag DN, Land SR, et al., National Surgical Adjuvant Breast, Bowel Project. Morbidity results from the NSAB B-32 trial comparing sentinel lymph node dissection versus axillary dissection. J Surg Oncol. 2010;102:111–118.
Leidenius M, Leivonen M, Vironen J, et al. The consequences of long-time arm morbidity in node-negative breast cancer patients with sentinel node biopsy or axillary clearance. J Surg Oncol. 2005;92:23–31
Tummel E, Ochoa D, Korourian S et al. Does Axillary Reverse Mapping Prevent Lymphedema After Lymphadenectomy? Ann Surg. 2017; 265(5):987-992