Intercostobrachial nerves as a novel anatomic landmark for dividing the axillary space in lymph node dissection.

Purpose. Our aim was to assess the feasibility of using the intercostobrachial nerves (ICBNs) as a possible new anatomic landmark for axillaries lymph node dissection in breast cancer patients. Background Data Summary. The preservation of ICBN is now an accepted procedure in this type of dissection; however, it could be improved further to reduce the number of postoperative complications. The axillary space is divided into lower and upper parts by the ICBN-a thorough investigation of the metastasis patterns in lymph nodes found in this area could supply new information leading to such improvements. Methods. Seventy-two breast cancer patients, all about to undergo lymph node dissection and with sentinel lymph nodes identified, were included in this trial. The lymph nodes were collected in two groups, from lower and upper axillary spaces, relative to the intercostobrachial nerves. The first group was further subdivided into sentinel (SLN) and nonsentinel (non-SLN) nodes. All lymph nodes were tested to detect macro- and micrometastasis. Results. All the sentinel lymph nodes were found under the intercostobrachial nerves; more than 10 lymph nodes were located in that space. Moreover, when lymph nodes macrometastasize or micrometastasize above the intercostobrachial nerves, we also observe metastasis-positive nodes under the nerves; when the lower group nodes show no metastasis, the upper group is also metastasis free. Conclusions. Our results show that the intercostobrachial nerves are good candidates for a new anatomic landmark to be used in lymph node dissection procedure.