Elevated preoperative neutrophil to lymphocyte ratio predicts survival following hepatic resection for colorectal liver metastases

Background: The neutrophil-lymphocyte ratio (NLR) provides an indicator of inflammatory status. An elevated NLR has been shown to be a prognostic indicator in primary colorectal malignancy. The aim of this study was to establish whether NLR predicts outcome in patients undergoing resection for colorectal liver metastasis. Design: Retrospective analysis of the white cell and differential counts for 440 patients undergoing liver resections for colorectal liver metastasis between January 1996 and January 2006. An NLR >= 5 was considered to be elevated. Results: Two hundred and eighty-nine mates and 151 females were included. Seventy-eight patients (18%) had an elevated NLR, 55 of whom died, giving elevated NLR a positive predictive value (PPV) for death of 71 %. Sixty of the 78 patients had recurrent disease giving raised NLR an PPV for recurrence of 78%. The 5-year survival for patients undergoing resection with high NLR was significantly worse than that for patients with normal NLR (22% vs. 43%, p < 0.0001). Univariate analysis of factors affecting survival revealed raised NLR, number of metastases >8, tumour size >5 cut and age >70 significantly affected outcome. All factors except tumour size remained significant predictors of term survival on multivariate analysis (NLR:HR = 2.261, CI = 1.654-3.129, p < 0.0001, metastases >8:HR = 1.611, CI = 1.006-2.579, p = 0.047, age >70:HR = 1.418, CI = 1.049-1.930, p = 0.027). Elevated NLR was found to be the sole positive predictor of recurrence on univariate analysis (HR = 4.521, CI = 2.475-8.257, p < 0.0001). Conclusion: Elevated NLR increases both risk of death and the risk of recurrence in patients who undergo surgery for CRLM. Preoperative NLR measurement may therefore provide a simple method of identifying patients with a poorer prognosis. (c) 2007 Elsevier Ltd. All rights reserved.