Kaplan-Meier survival curves for OS and DFS in CRC patients. (A) OS according to the NLR; (B) DFS according to the NLR; (C) OS according to IL-6 level; (D) DFS according to IL-6 level; (E) OS according to the NLR + IL-6 level; (F) DFS according to the NLR + IL-6 level. The prognostic scores of the NLR were assigned to scores of 1 (≥2.99) or scores of 0 (<2.99). The prognostic scores of IL-6 level were assigned to scores of 1 (≥213.83 pg/mL) or scores of 0 (<213.83 pg/mL). The prognostic scores of the combination of the NLR and IL-6 level (COCN) were scores of 2 (NLR ≥2.99 and IL-6 ≥213.83 pg/mL), 1 (NLR ≥2.99 or IL-6 ≥213.83 pg/mL), or 0 (neither NLR ≥2.43 nor IL-6 ≥213.83 pg/mL). NLR, neutrophil to lymphocyte ratio; IL-6, interleukin-6; CRC, colorectal cancer; OS, overall survival; DFS, disease-free survival.