Objective To investigate the predictive value of preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR) and systemic immune-inflammation index (SII) for postoperative recurrence after radical resection of colorectal cancer.

Methods A total of 150 patients who underwent radical resection for colorectal cancer were enrolled and followed up for 3 years. They were divided into the recurrence group (n = 42) and the non-recurrence group (n = 108) based on recurrence status. Preoperative NLR, PLR, LMR and SII were measured. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive value of these indicators for postoperative recurrence after radical resection of colorectal cancer.

Results Compared with the non-recurrence group, the recurrence group exhibited significantly elevated preoperative NLR, PLR and SII levels, and decreased LMR level (P ＜ 0.01). Multivariate logistic regression analysis demonstrated that NLR OR = 7.079, 95%CI: 1.269–39.497, PLR OR = 1.059, 95%CI: 1.021–1.103 and SII OR = 1.006, 95%CI: 1.001–1.012 were independent risk factors for recurrence. The results of ROC curve analysis showed that the area under the curve (AUC) of the combined four indicators for predicting recurrence was 0.927, which was higher than that of single indicators NLR (0.820), PLR (0.800), LMR (0.756) and SII (0.818).

Conclusions Preoperative NLR, PLR, LMR and SII have high predictive value for postoperative recurrence after radical resection of colorectal cancer.