Abstract:【Abstract】Objective To explore the diagnostic value of red cell distribution widthtolymphocyte ratio (RLR) for colorectal cancer, and compare its difference with CEA and CA199 in the diagnosis of colorectal cancer. Methods A total of 501 patients with colorectal cancer(colorectal cancer group), 404 patients with colorectal polyps(colorectal polyp group) and 424 healthy subjects control group were selected from the Affiliated Hospital of Xuzhou Medical University from June 2012 to May 2020. The levels of RLR, CEA and CA199 in peripheral blood of the three groups of subjects were detected and compared with RLR, CEA and CA199 The diagnostic efficiency of the three for colorectal cancer, and the Spearman correlation between RLR and CEA and CA199 in the colorectal cancer group was analyzed. Results The level of RLR in peripheral blood of colorectal cancer was higher than that of colorectal polyp group and normal control, and the difference was statistically significant (P<005). RLR is positively correlated with CEA and CA199, and Spearman's correlation coefficients are 0128 and 0227 (P<005). Through the ROC curve, the sensitivities corresponding to the best cutoff values of RLR, CEA, and CA199 are: 557%, 637%, 397%, and the specificities are 676%, 792%, and 87.9%, respectively. The RLR of patients with distant organ metastasis was significantly higher than that of patients without organ metastasis, and the difference was statistically significant (P<005). ConclusionThe sensitivity and specificity of a single detection of RLR are low. The sensitivity of RLR combined with CEA and CA199 detection in the diagnosis of colorectal cancer is improved, which is conducive to the early diagnosis and prognosis of colorectal cancer.