Prognostic utility of blood inflammation biomarkers before and after treatment on the survival of patients with locally advanced non‐small cell lung cancer undergoing stereotactic body radiotherapy

Background and Objective The neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) were significant and succinct indicators of systemic inflammation. We assessed the influence of stereotactic body radiotherapy (SBRT) on NLR and PLR in patients with locally advanced non‐small cell lung cancer (LA‐NSCLC). Methods We reviewed the medical data of patients with LA‐NSCLC who underwent SBRT between 1 January 2013 and 31 December 2018. NLR and PLR values recorded at pre‐ and post‐SBRT were examined. We assessed the correlation between pre/post‐SBRT NLR and PLR and survival outcomes. The decision tree evaluation was conducted using Chi‐square automatic detection. Results In total, 213 patients were included in the study with a median follow‐up duration of 40.00 (ranging from 5.28 to 100.70) months. Upon dichotomization by a median, we identified that post‐SBRT NLR > 5.5 and post‐SBRT PLR > 382.0 were negatively associated with shorter overall survival (OS). In the multivariate assessment, post‐SBRT PLR > 382.0 was the only factor. Based on post‐SBRT PLR, tumor locations, and tumor stage, we categorized patients into low, medium, or high‐risk groups. Conclusions Post‐SBRT PLR > 382.0 correlated with survival in patients undergoing SBRT. The decision tree model might play a role in future risk stratification to guide the clinical practice of individualized SBRT for LA‐NSCLC.