Abstract P2-05-15: The lymph node ratio as an independent prognostic factor for node-positive triple-negative breast cancer

Abstract

Abstract Purpose: To evaluate the prognostic value of the lymph node ratio (LNR) in patients with axillary lymph node-positive triple-negative breast cancer (TNBC). Patients and methods: Based on X-tile plots, we classified women into low-, medium-, and high-risk LNR groups. Univariate and multivariate Cox proportional hazards regression analyses for overall survival (OS), breast cancer-specific survival (BCSS) and disease-free survival (DFS) were performed. The prognostic efficacy of the LNR was investigated in the first cohort from the Surveillance, Epidemiology, and End Results (SEER) database (n=4114) and was further validated in an independent cohort from Fudan University Shanghai Cancer Center (n=417). Results: The patients were classified into low- (≤0.30), medium- (0.30 to 0.70) and high-risk (>0.70) LNR groups. Multivariate analysis revealed that the LNR was an independent predictor of OS (hazard ratio (HR) for high-risk LNR: 3.24; 95% confidence interval (CI): 2.56 to 4.09) and BCSS (HR for high-risk LNR: 3.57; 95% CI: 2.76 to 4.62) in the SEER population and also for DFS (HR for high-risk LNR: 4.29; 95% CI: 2.24-8.21) in the validation population. Subgroup analysis revealed that patient classification according to the LNR could discriminate among groups of patients with different survival rates based on pN staging. Effect of Lymph Node Ratio and pN Classification on Survival Among Patients from SEERVariableOSBCSS HR a(95% CI)PHR a(95% CI)PLymph node ratio Low,≤0.301-1-Medium, >0.30 and ≤0.702.05(1.63-2.59)<0.0012.26(1.75-2.92)<0.001High,>0.703.24(2.56-4.09)<0.0013.57(2.76-4.62)<0.001pN N11-1-N21.53(1.21-1.93)<0.0011.63(1.27-2.10)0.001N32.72(2.14-3.46)<0.0012.97(2.29-3.85)<0.001a Cox proportional hazards model. Hazard ratios are adjusted for age, race, histologic grade, tumor size, surgery type and radiotherapy. Conclusion: The LNR shows potential for use as an additional prognostic factor for TNBC patients with positive lymph node involvement. Considering the heterogeneity of TNBC, use of the LNR might allow for optimization of the pN staging system, and this ratio should be considered when making treatment decisions. Citation Format: He M, Jiang Y-Z, Tang L-C, Chen Y-L, Shao Z-M, Di G-H. The lymph node ratio as an independent prognostic factor for node-positive triple-negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-15.