The Clinical Impact of Combining Neutrophil-to-Lymphocyte Ratio with Sarcopenia for Improved Discrimination of Progression-Free Survival in Patients with Colorectal Cancer

Abstract

This study aimed to evaluate the clinical impact of combined sarcopenia and inflammation classification (CSIC) in patients with colorectal cancer (CRC). The skeletal muscle index (SMI) and neutrophil-to-lymphocyte ratio (NLR) were measured in 1270 patients who underwent surgery between January 2005 and April 2014. A Cox proportional hazards model was used to evaluate the correlation of sarcopenia, NLR, and CSIC, with progression-free survival (PFS). The integrated area under the curve (iAUC) was used to compare the discriminatory performance of each model. Using the cut-off values for SMI suggested by Martin et al. and for an NLR of 2.26, the CSIC was defined as follows: nonsarcopenia with low NLR (group 1), nonsarcopenia with high NLR (group 2), sarcopenia with low NLR (group 3), and sarcopenia with high NLR (group 4). Sarcopenia alone was not statistically significant. Multivariate analysis identified that CSIC (group 4 vs. group 1; hazard ratio (HR), 1.726; 95% CI, 1.130-2.634; p = 0.011) and NLR (HR, 1.600; 95% CI, 1.203-2.128; p = 0.001) were independently associated with PFS. The CSIC improved the prediction accuracy of PFS compared with NLR (iAUC mean difference = 0.011; 95% CI, 0.0018-0.028). In conclusion, the combination of sarcopenia and NLR could improve prognostic accuracy, and thus compensate for the limitation of sarcopenia.