e20634 Background:The tumor immune environment is integral in lung cancer progression. Cancer cells attract neutrophils through chemokine signaling pathyways into the tumor stroma. Neutrophils promote angiogenesis, metastasis and inhibit apoptosis whereas lymphocytes assist with tumor defense. Increased peritumoral neutrophil-to-lymphocyte ratio (NLR) has been shown to mediate T cell anergy and tumor immune evasion. In solid tumor pre-clinical models, elevated blood NLR correlates with increased tumor neutrophil infiltration and decreased CD3(+) T-cell infiltration. Immunotherapy is a promising anticancer strategy in Non-Small Cell Lung Cancer (NSCLC). We hypothesized that peripheral blood NLR could serve as a predictive marker for clinical benefit (CB) from this intervention. Methods:A single institution retrospective analysis of 81 patients with NSCLC treated with Nivolumab from July 2015 to November 2016. Each patient’s NLR was calculated prior to starting Nivolumab. A cut-off of 5 categorized NLR as high or low based on prior studies. The presence or absence of CB (objective response or stable disease per RECIST 1.1) after at least 3 months of therapy was determined. Descriptive statistics were utilized to summarize the data. Fischer exact test was used to compare proportions and student t test to compare means. Results:79 patients were included. 54 (68%) had low NLR and 25 (31.6%) had high NLR. 44 patients (81.48%) in the low NLR group and 7 (28%) in the high NLR group experienced CB (28%) at 3 months. This difference was statistically significant (P = 0.0001). The mean time to progression(TTP) for the low NLR population was 5.53 months, as compared to 2.39 months in the high NLR group( p = 0.0001) (95% confidence interval 1.59 to 4.55).The mean TTP in the CB cohort was 6.42 months in the low NLR group and 4.43 months in the high NLR group (p = 0.0052 ) (95% CI 0.61 to 3.39). Conclusions:The immune response to cancer is lymphocyte dependent. In our study, the majority of patients with low NLR experienced CB from Nivolumab whereas most of the patients with elevated NLR did not. NLR as a predictive biomarker should be further investigated in large prospective studies.
Neutrophil-to-lymphocyte ratio after four weeks of nivolumab administration as a predictive marker in patients with pretreated non-small-cell lung cancer