Abstract P4-11-41: Pretreatment neutrophil/lymphocyte ratio and overall survival in African American and white breast cancer patients

Abstract

Abstract Previous studies have shown that the pretreatment neutrophil/lymphocyte ratio (NLR) is an independent predictor of mortality in breast cancer patients. Our aim was to further study the relationship between pretreatment NLR and overall survival in African American and white breast cancer patients treated at an academic cancer center. Electronic medical records were reviewed for 589 patients treated between 2002 and 2011, and pretreatment NLR data, determined at an average of 12 days prior to the initiation of cancer treatment, were available from 217 African American and 218 white patients. Other clinical and patient data were obtained from the hospital tumor registry, with annual follow-up for vital status. There were a total of 102 deaths over a mean follow-up of 59 months. For data analysis, patients were divided into quartiles based on their NLR (Q1: <1.54; Q2: 1.54≤2.0; Q3: 2.0≤2.79; and Q4: ≥ 2.79). Patients in the highest quartile of pretreatment NLR showed an increase in overall mortality compared to those in the lowest quartile, with a hazard ratio (HR) of 2.4 (p<0.005). After adjustment for age, tumor stage, and grade, the pretreatment NLR remained significantly associated with overall mortality (HR=2.1, p=0.03). Further adjustment for race, body mass index (BMI) and smoking increased the effect size (HR=3.2, p<0.01), but only half patients remained in the analysis due to incomplete data on BMI and smoking. In our study, race, but neither BMI nor smoking, was associated with pretreatment NLR values: African American patients had higher pretreatment NLR values than white patients regardless of stage. In a stratified analysis by race, HRs for overall mortality associated with the highest quartile of pretreatment NLR versus the remaining three quartiles combined were 2.5 (p<0.01) among African Americans and 1.6 (p=0.24) among white patients, although the interaction between race and pretreatment NLR was not statistically significant. Our data confirm previous findings that pretreatment NLR, a marker of systemic inflammatory response, is unfavorably associated with overall survival in breast cancer patients, and also suggest that the association may be more evident among African American patients whose levels were generally higher than white breast cancer patients. Future studies are warranted to investigate the prognostic utility of pretreatment NLR in different racial groups and whether a heightened systemic inflammatory response is an underlying contributor to racial difference in breast cancer outcomes. Citation Format: Joseph C Rimando, Jeff Campbell, Jae Hee Kim, Sangmi Kim. Pretreatment neutrophil/lymphocyte ratio and overall survival in African American and white 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 P4-11-41.