319P - Characteristics of Breast Cancer Patients with False-Negative Sentinel Node Biopsy

Abstract

ABSTRACT Aim: There are only limited studies that analyzed the clinical significance of false-negative (FN) in sentinel node biopsy (SNB) with sufficient sample size. The aim of this study was to identify the risk factors for FN in SNB and to analyze the clinical significance of that in patients with breast cancer. Methods: Patients with invasive breast cancer who underwent SNB followed by axillary node dissection between 1995 and 2013 were retrospectively identified. We excluded patients with ductal carcinoma in situ or those who had recieved preoperative chemotherapy. A total of 189 patients with FN in SNB were compared to 413 women with true-negative (TN) in SNB. Logistic regression analysis was used to identify risk factors associated with FN result and Cox regression analysis was performed to assess the clinical impact of that. Results: Histologic type, lymphovascular invasion, location of main lesion, tumor size, and administration of adjuvant chemotherapy were associated with FN in SNB. Multivariate analysis showed that ductal carcinoma, tumor located at upper outer quadrant, and larger tumor were significant independent risk factors for FN; adjusted odds ratios representing 2.82 (95% CI: 1.58 to 5.04), 1.74 (95% CI: 1.22 to 2.49), and 1.29 (95% CI: 1.08 to 1.53), respectively. Patients with FN in SNB showed worse disease-free survival (DFS) than those with TN, corresponding to 5-year DFS rates of 86.4% and 94.7%, respectively and an adjusted hazard ratio of 3.87 (95% CI: 1.84 to 8.12; p Conclusions: This study showed that patients with FN in SNB presented worse prognosis than those with TN even with adjuvant treatment. In patients with ductal carcinoma, with larger tumor size, and with tumors located at the upper outer quadrant, it would be necessary to make an effort to find out metastatic non-sentinel nodes with a suspicion after SNB. Disclosure: All authors have declared no conflicts of interest.