Opinion Paper/CommentarySentinel Lymph Node Biopsy in Breast Cancer Indications, Contraindications, and ControversiesManca, Gianpiero MD; Rubello, Domenico MD; Tardelli, Elisa MD; Giammarile, Francesco MD; Mazzarri, Sara MD; Boni, Giuseppe MD; Chondrogiannis, Sotirios MD; Marzola, Maria Cristina MD; Chiacchio, Serena MD; Ghilli, Matteo MD; Roncella, Manuela MD; Volterrani, Duccio MD; Colletti, Patrick M. MDAuthor Information From the *Regional Center of Nuclear Medicine, Hospital University of Pisa, Pisa; †Department of Nuclear Medicine, S. Maria della Misericordia Hospital, Rovigo, Italy; ‡Biophysique, Faculté de Médecine Lyon Sud, Médecine Nucléaire, Hospices Civils de Lyon, Lyon, France; §Unit of Senology, Hospital University of Pisa, Pisa, Italy; and ∥Department of Radiology, University of Southern California, Los Angeles, CA. Received for publication July 16, 2015; revision accepted July 19, 2015. Conflicts of interest and sources of funding: none declared. Correspondence to: Domenico Rubello, MD, Via Tre Martiri 140; 45100 Rovigo, Italy. E-mail: email@example.com. Clinical Nuclear Medicine: February 2016 - Volume 41 - Issue 2 - p 126–133 doi: 10.1097/RLU.0000000000000985 Buy Metrics Abstract Axillary lymph node status, a major prognostic factor in early-stage breast cancer, provides information important for individualized surgical treatment. Because imaging techniques have limited sensitivity to detect metastasis in axillary lymph nodes, the axilla must be explored surgically. The histology of all resected nodes at the time of axillary lymph node dissection (ALND) has traditionally been regarded as the most accurate method for assessing metastatic spread of disease to the locoregional lymph nodes. However, ALND may result in lymphedema, nerve injury, shoulder dysfunction, and other short-term and long-term complications limiting functionality and reducing quality of life. Sentinel lymph node biopsy (SLNB) is a less invasive method of assessing nodal involvement. The concept of SLNB is based on the notion that tumors drain in an orderly manner through the lymphatic system. Therefore, the SLN is the first to be affected by metastasis if the tumor has spread, and a tumor-free SLN makes it highly unlikely for other nodes to be affected. Sentinel lymph node biopsy has become the standard of care for primary treatment of early breast cancer and has replaced ALND to stage clinically node-negative patients, thus reducing ALND-associated morbidity. More than 20 years after its introduction, there are still aspects concerning SLNB and ALND that are currently debated. Moreover, SLNB remains an unstandardized procedure surrounded by many unresolved controversies concerning the technique itself. In this article, we review the main indications, contraindications, and controversies of SLNB in breast cancer in the light of the most recent publications. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.