Editorial
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Oncol. Dec 10, 2015; 6(6): 202-206
Published online Dec 10, 2015. doi: 10.5306/wjco.v6.i6.202
Sentinel lymph node metastasis after neoadjuvant treatment in breast cancer: Any size matters?
Isabel T Rubio
Isabel T Rubio, Breast Surgical Oncology Unit, Breast Cancer Center, Hospital Universitario Vall d’Hebron, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
Author contributions: Rubio IT had contributed to all parts of the manuscript.
Conflict-of-interest statement: No conflict of interest to disclose.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Isabel T Rubio, MD, PhD, Breast Surgical Oncology Unit, Breast Cancer Center, Hospital Universitario Vall d’Hebron, Universitat Autònoma de Barcelona, Paseo Vall d’Hebron 119, 08035 Barcelona, Spain. irubio@vhio.net
Telephone: +34-93-2894286
Received: May 25, 2015
Peer-review started: May 27, 2015
First decision: August 4, 2015
Revised: August 9, 2015
Accepted: September 25, 2015
Article in press: September 28, 2015
Published online: December 10, 2015
Processing time: 198 Days and 4 Hours
Abstract

One of the advantages of neoadjuvant chemotherapy (NAC) treatments is its ability to convert patients who need a mastectomy in breast conservative surgery. NAC has also increased the conversion of node positive patients into node negative in around 40% allowing the use of sentinel node biopsy (SLN) in this setting. Timing of SLN biopsy after NAC has been a subject of debate. In patients with clinically node negative before NAC, rates of success and false negative rates of SLN after NAC are similar to those in the adjuvant setting, so SLN after NAC in previous negative axilla has been incorporated in the staging of the axilla. More controversial is its use in patients with positive axillary nodes before NAC who convert to node negative after NAC. Several randomized studies have reported the identification rates and the false negative rates of the SLN after NAC, concordant in the importance of surgical technique. As there is an agreement in the abandon of the immunohistochemistry (IHC) for SLN in the adjuvant setting as SLN IHC detected metastasis appear to have no impact on overall survival, in patients with SLN after NAC the inclusion of isolated tumor cell (ITC) as positive nodes lowers the false negative rates of the technique, suggesting the importance of assessing the SLN by IHC after NAC and considering it as residual disease. Longer follow up is needed to determine the prognostic implications of ITC in the SLN after NAC.

Keywords: Sentinel node; Metastasis; Neoadjuvant treatment; Breast cancer

Core tip: One of the advantages of neoadjuvant chemotherapy treatment in breast cancer is to downstage positive axillary nodes to negative. Postneoadjuvant sentinel lymph node (SLN) has been increasingly used and randomized studies in patients with positive axillary nodes who convert to node negative have shown that false negative rates are highly influenced by the surgical technique. Information from these studies has shown that isolated tumor cells in the SLN, when considered as positive nodes, lower false negative rates. Whether any residual disease in the SLNs may have prognostic implications warrants further research.