Abstract P2-01-05: Correlation of percutaneously biopsied axillary lymph nodes marked with black tattoo ink prior to neoadjuvant chemotherapy with sentinel lymph nodes in breast cancer patients

Introduction: Sonographic evaluation of the axilla and percutaneous biopsy of abnormal lymph nodes with fine needle aspiration (FNA) or core needle biopsy (CNB) has become more common practice in patients with newly diagnosed breast cancer prior to neoadjuvant chemotherapy (NAC). Sentinel lymph node (SLN) biopsy is considered the gold standard for axillary staging in clinically node negative breast cancer patients. Currently, there is no clear correlation of sonographically detected abnormal lymph nodes and open surgical assessment. We conducted an exploratory pilot study which marked suspicious axillary lymph nodes with black tattoo ink at the time of percutaneous needle biopsy prior to NAC. Black nodes visualized during axillary surgery were evaluated in comparison to SLNs. Methods: Breast cancer patients with clinical and/or sonographically suspicious axillary lymph nodes prior to NAC were included in the study. Following FNA or CNB biopsy of node, 0.1 to 0.5 ml of a sterile, highly purified, biocompatible fine carbon suspension (Spot™) was injected into the cortex of the lymph node and adjacent soft tissue. A total of 12 patients were injected with black ink prior to NAC. Intraoperative presence of black pigment was assessed and correlation between sentinel and tattooed nodes were evaluated. Results: Nine patients had a positive percutaneous lymph node biopsy prior to NAC. The average number of days that elapsed between injection and to surgery was 130 days. A successful SLN procedure was performed in all patients. A black tattooed node was identified in all patients and correlated to a SLN. 7 patients were down-staged in the axilla and 6 patients did not go onto completion axillary dissection. One patient with a negative SLN had a completion axillary dissection, but no additional positive lymph nodes were found. Four patients with positive SLN had a completion axillary dissection (1 of whom was a false negative percutaneous biopsy). In all four patients, the positive sentinel node contained visible black ink. There was one patient who had an additional positive sentinel node, which was not black. Two axillary dissections contained additional positive nodes. Conclusion: Black ink tattooing with sterile black ink (Spot™), successfully marked suspicious lymph nodes prior to NAC. These correlated to a SLN. In node positive patients with a partial response in the axillary lymph nodes following neoadjuvant chemotherapy, previously marked, black-inked node proved to be the persistent positive node. Tattooing of lymph nodes at the time of percutaneous biopsy may improve the accuracy of surgical axillary staging by aiding in the intra-operative identification of previously biopsied nodes. Citation Format: Nicole Choy, Jafi Lipson, Sunita Pal, Debra Ikeda, Long Trinh, Kimberly Allison, Michael Ozawa, Amanda Wheeler, Irene Wapnir. Correlation of percutaneously biopsied axillary lymph nodes marked with black tattoo ink prior to neoadjuvant chemotherapy with sentinel lymph nodes in breast cancer patients [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-01-05.