Abstract PS4-17: Association of neutrophil-to-lymphocyte ratio with pathological complete response in locally advanced breast cancer

Abstract Background: Neutrophil-to-lymphocyte ratio (NLR) has emerged as a potential inflammatory blood biomarker for breast cancer (BC) outcomes. Prior analysis suggests that NLR is a reliable prognostic factor for patients with locally advanced breast cancer (LABC) receiving adjuvant chemotherapy. However, the prognostic value in patients receiving neoadjuvant chemotherapy (NAC) remains unclear. We aimed to evaluate the association of baseline NLR with pathological complete response (pCR) among patients with LABC treated with NAC. Methods: We retrospectively analyzed 253 patients with stage II and III BC that received NAC followed by surgery at Montefiore Einstein Cancer Center from 2005 through 2017, and had information regarding baseline NLR and pCR at surgery. Demographic, clinicopathological, laboratory and treatment characteristics were obtained from electronic medical records. Laboratory parameters included absolute neutrophil count and absolute lymphocyte count. pCR was defined as absence of residual invasive carcinoma in both the breast and the lymph nodes (ypT0/ypN0 or ypTis/ypN0) at the time of surgery. The association between NLR and pCR was assessed using the multivariate logistic regression model. The association between NLR and disease free survival (DFS) and overall survival (OS) was assessed using Cox proportional hazards models. Results: Median age at diagnosis was 54 years [interquartile range (IQR)=45-63]. Patients were predominantly non-Hispanic (58%). The most common race was Black (49%) followed by White (32%) and Asian (6%). Pre/perimenopausal and postmenopausal status corresponded to 42% and 59% of patients, respectively. The most common histological subtype was ductal (88%) followed by lobular (7%) adenocarcinoma. High, intermediate and low histological grades were seen in 57%, 36% and 2%, respectively. Triple negative, human epidermal growth factor receptor 2-HER2(+), and hormone receptor-HR(+)/HER2(-) tumors corresponded to 39%, 31% and 30% of patients, respectively. Taxanes and anthracyclines were administered to 96% and 68% of patients, respectively. Mastectomy (63%) was the most common type of surgery followed by breast conserving (37%) surgery. pCR was achieved in 30% of patients. Median NLR was 2.2 [IQR=1.6-3.1] and dichotomized into NLRHIGH (>=2.2) and NLRLOW (<2.2). In the bivariate analysis, there was no statistically significant association between NLRHIGH vs. LOW and pCR (p=0.78). When adjusted for age, race, histological grade, HR status and HER2 status, no statistically significant association was found between NLR and pCR (Odds ratio: 0.82, p=0.51). When adjusted for age, race, histological grade, HR status and HER2 status, no statistically significant association was found between NLR and DFS (Hazard ratio (HR): 0.75, p=0.3) or OS (HR: 0.61, p=0.19). Conclusions: In our study, the baseline NRL was not an independent prognostic factor for pCR, DFS or OS in patients with stage II and III BC treated with NAC. These findings are consistent with prior studies. Patients of Black race have lower baseline neutrophil counts, which could lead to different NLR values than other racial groups. Notably, our population was predominantly Black, in which scarce data exists concerning the association between NLR and BC outcomes. Further studies are needed to elucidate the prognostic value of NLR in the neoadjuvant setting among multiracial groups. Citation Format: Laura S Munoz-Arcos, Ashley Weiner, Jee-Young Moon, Xionan Xue, Jesus Anampa-Mesias. Association of neutrophil-to-lymphocyte ratio with pathological complete response in locally advanced breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS4-17.