Objective: Increasing neutrophil/lymphocyte ratios on preoperative blood tests have been associated with worse survival after resection of colorectal cancer. We sought to determine factors associated with increasing neutrophil/lymphocyte ratios and the stage-adjusted prognostic effect in patients undergoing resection for non-small cell lung cancer.
Methods: We performed a retrospective review of patients undergoing complete resection for non-small cell lung cancer between 1999 and 2005. Data acquisition was through patient medical records, blood results recorded on admission before surgical intervention, and follow-up by National Health Service database searches and hospital records. Cox proportional hazards regression was used to estimate the effect of neutrophil/lymphocyte ratio on stage-adjusted survival.
Results: During the study period, 178 patients underwent pulmonary resection. Of 177 patients, the majority were male 104 (59%), with a mean age of 63 years (standard deviation, 10 years). The median follow-up time was 29 months (interquartile range, 8-56 months), and overall survival was 83% and 54% at 1 and 5 years, respectively. Higher stage was the only factor found to be associated with increasing neutrophil/lymphocyte ratios (P = .019). Total white cell count (P = .990) and neutrophil count (P = .490), age (P = .290), and cell type (P = .490) were not significant predictors of mortality. On multivariable analysis after adjusting for stage, increasing neutrophil/lymphocyte ratios (hazard ratio, 1.10; 95% confidence interval, 1.03-1.17; P = .004) remained an independent prognostic indicator.
Conclusions: Increasing preoperative neutrophil/lymphocyte ratios are associated with higher stage but remain an independent predictor of survival after complete resection for primary lung cancer and are a potential biomarker to stratify high risk of death in patients with stage I disease.