Neutrophil-To-Lymphocyte Ratio As A Response Predictor To Immune Checkpoint Inhibitors In Non-Small Cell Lung Cancer

Background: The immune checkpoint inhibitors (ICIs) have changed the treatment of non-small cell lung cancer (NSCLC) but there are few predictive and prognostic biomarkers. Even with high levels of PD-L1 expression, some patients do not benefit from anti-PD1 or PD-L1 inhibitors. Neutrophil-to-lymphocyte ratio (NLR) has been shown to be a potential biomarker in these settings. Methods: The primary endpoint was to evaluate NLR relation with progression-free survival (PFS) and overall survival (OS). Secondary endpoints were analysis of population demographics and major toxicities to ICIs. Unicentric, retrospective clinical study, including all patients with advanced NSCLC treated with ICIs. NLR is calculated by dividing the absolute neutrophil count by the absolute lymphocyte count from a complete blood count with differential. NLR was defined as high when > 2,375 and low when ≤ 2,375, using ROC curve. PFS was calculated by the Kaplan-Meier method. Results: Sixty-nine patients treated with ICIs from January 2016 until October 2020 were analysed, with median age of 63 years old, 66.7% were males, 33.3% non-smokers, 62.3% had an ECOG PS 0, and 58% had stage IV at diagnosis. Thirty-two (46.4%) patients were receiving ICIs as second line treatment. Thirty-three patients (47.8) received pembrolizumab, thirty-two (46.4%) nivolumab and four (5.8%) atezolizumab. The median number of treatments of ICIs were 9 (1–105). Median PFS was 7 months (3.0–10.9), with no significative statistical differences between the high and low NLR groups. Median PFS of patients treated with nivolumab was 3 months (1.9–4.1), with pembrolizumab was 15 months (4.7–25.3) and with atezolizumab was 3 months. Immunomediated adverse events (AEs) G3/4 were present in 6 patients and required ICIs suspension in all cases. One toxic death with pembrolizumab (1 cycle) was observed after hepatic failure. Conclusions: Our results were probably due to small population in this study and it is crucial to search for biomarkers to predict ICIs response. These biomarkers will help to define which patients will benefit the most from these therapeutics. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.