Abstract P3-01-07: Second axillary sentinel lymph node biopsy for breast tumor recurrence: Instituto Alexander Fleming experience in Buenos Aires, Argentina
Authors: Maino M , Fabiano V , Ponce C , Loza M , Costanzo V , Nervo A , Nadal J , Mysler D , Amat M , Coló F , Loza J , Chacón R 
Published: May 2016

Abstract
Sentinel Lymph Node Biopsy (SLNB) is the standard technique for axillary staging of patients with operable breast cancer and a clinically negative axilla because it avoids unwarranted axillary dissection and consequently reduces postoperative morbidity.
Purpose: The aim of this study is to determinate the feasibility and accuracy of the second SLNB for patients with ipsilateral breast cancer recurrences with clinically negative axilla, who were treated previously with breast surgery and study of the axilla.
Methods: Retrospective review of the database of the Instituto Alexander Fleming. Between October 2009 and October 2014, 1029 patients with diagnosis of breast cancer required surgery. The study included 26 patients with the diagnosis of operable local breast cancer recurrence, who had previously undergone axillary surgery either as SLNB, sampling or axillary lymph node dissection (ALND). They subsequently underwent additional breast surgery and a second SLNB.
Results: The mean age of the ipsilateral breast cancer recurrences was 59.23 years (range: 32-87) and the most common histologic subtype was invasive ductal carcinoma in 22 patients (84.6%) and 4 patients (15.4%) with invasive lobular carcinoma. 4 patients (15.4%) had previously ALND or sampling and 22 patients (84.6%) SLNB. The identification rate of the second SLNB was 92.31%. Only 2 patients were not identify, one patient with a previous axillary sampling and another one with previous SLNB. In those patients the ALND was performed and the axilla was negative. Lymphoscintigraphy failed to identify any SLN in 6 patients (23%), 2 patients which were not identify and 4 patients only detected with patent blue. The average number of nodes removed at second SLNB was 1.8 (range: 1-5). Second SLNBs were negative in 21 patients (80.8%), and macrometastasis disease was identified in 2 patients and complete ALND was performed.
In 1 patients additional extra-axillary aberrant drainages was observed in the contralateral axilla and interpectoral, and other 3 patients had aberrant drainage in the contralateral axilla (1 patient), internal mammary regions (1 patient), and interpectoral (1 patient). Aberrant drainage pathways were not routinely dissected. Only those accessible during surgery were removed.
The median time between first surgery and ipsilateral breast tumor recurrence was 7.19 years (range: 1-22). The disease free survival (DFS) was 9.16 years (range: 2.25-24).
Conclusion: In the present serie we show a high identification rate of 92.31% in the second SLNB, comparable with other international series published in the literature (range: 51-97%). A second SLNB should be considered for patients with ipsilateral breast tumor recurrence who underwent conservative surgery and have clinically negative axilla. The procedure is technically feasible and accurate for selected patients, and avoids unnecessary ALND. Extra-axillary sentinel lymph node localization rates are higher than for primary SLNB but the clinical significance and management of extra-axillary nodes needs to be clarified.
Citation Format: Maino M, Fabiano V, Ponce C, Loza M, Costanzo V, Nervo A, Nadal J, Mysler D, Amat M, Coló F, Loza J, Chacón R. Second axillary sentinel lymph node biopsy for breast tumor recurrence: Instituto Alexander Fleming experience in Buenos Aires, Argentina. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-07.