_1630698920 1630698920 brea akaviani@archbreastcancer.com Farname Inc Archives of Breast Cancer Arch Breast Cancer 2383-0433 04 15 2021 Kelly S Myers Sachin Aggarwal Eniola T Oluyemi Mehran Habibi Emily B Ambinder Armina Azizi Parvinder Sujlana Jessica Hung Nagi Khouri David Eisner Philip A Di Carlo Ashley M Cimino-Mathews Melissa S Camp Background: Pre-operative localization options in the axilla are limited. This study aimed to explore the utility of pre-operative localization of axillary lymph nodes using tattoo ink with multidisciplinary correlations.Methods: In this prospective, Institutional Review Board (IRB)-approved study, 19 lymph nodes in 17 patients underwent pre-operative localization with ultrasound-guided injection of Spot tattoo ink. The success rate of intraoperative identification of the tattooed node as well as the frequency in which the tattooed node was also a sentinel node were recorded. Radiologic, surgical and pathologic images were collected. Results: Tattoo ink localization was successful in 16/17 (94.1%) of patients. Tattoo ink did not hinder pathologic evaluation in any cases but was taken up by additional adjacent nodes in 1/17 successful localizations (5.9%). Successful sentinel lymph node biopsy (SLNB) occurred in 13 patients in whom 14 lymph nodes underwent pre-operative tattoo ink localization. Nine of the 14 (64.2%) tattooed lymph nodes were also a sentinel node.Conclusion: In this study, pre-operative localization of axillary lymph nodes with tattoo ink was highly successful In patients undergoing SLNB, a significant number of the tattooed nodes were not sentinel nodes (35.8%), suggesting the importance of targeted lymph node excision in addition to SLNB. 04 15 2021 143 148 http://creativecommons.org/licenses/by-nc/4.0 10.32768/abc.202182143-148 https://www.archbreastcancer.com/index.php/abc/article/view/379 https://www.archbreastcancer.com/index.php/abc/article/download/379/487 https://www.archbreastcancer.com/index.php/abc/article/download/379/487