Abstract: Objective   To investigate the value of peripheral blood penetrating cytokine 3 (PTX-3) combined with miR-486-3p in predicting postoperative recurrence and metastasis before laparoscopic radical resection of colorectal cancer.  Methods   A total of 157 patients with laparoscopic radical resection of colorectal cancer were selected from March 2018 to May 2021.The levels of PTX-3 and miR-486-3p in peripheral blood of all patients were detected before surgery,and patients were followed up for 1 year after surgery.Patients were divided into relapse-metastasis group and non-relapse-metastasis group according to the recurrence and metastasis after surgery.The clinical data of the two groups were compared,and the factors related to recurrence and metastasis after laparoscopic radical resection of colorectal cancer were analyzed by multivariate Logistic regression.The receiver operating characteristic curve (ROC) was plotted,and the area under the curve (AUC) was used to evaluate the predictive value.  Results   After 1 year’s follow-up,5 of 157 patients were lost to follow-up,with a follow-up rate of 96.82%.Among them,recurrence and metastasis was 28 patients,recurrence and metastasis rate was 18.42%,and the remaining 124 patients had no recurrence and metastasis.Age ≥60 years old,lymph node metastasis,stage Ⅲ,low differentiation,tumor diameter ≥5cm,preoperative platelet count,CEA,glycoantigen 19-9 (CA19-9),peripheral blood PTX-3,miR-486-3p levels in the relapsed and metastatic group were higher than those in the non-relapsed and metastatic group (P<0.05).Logistic regression analysis showed that lymph node metastasis,stage Ⅲ,low differentiation,preoperative peripheral blood PTX-3 level and preoperative peripheral blood miR-486-3p level were the factors affecting recurrence and metastasis after laparoscopic radical resection of colorectal cancer (P<0.05).ROC curve results show that,The AUC values (95%CI) of peripheral blood PTX-3,miR-486-3p and their combination in predicting recurrence and metastasis after laparoscopic radical resection of colorectal cancer were 0.746 (0.643-0.833),0.805 (0.707-0.881) and 0.868 (0.779-0.930),respectively (P<0.0 5),and the combined AUC values were higher than those detected alone (P<0.05).Preoperative peripheral blood PTX-3 combined with peripheral blood miR-486-3p predicted the AUC value of recurrence and metastasis after laparoscopic radical resection of colorectal cancer was higher than that of lymph node metastasis and stage Ⅲ combined with low differentiation (P<0.05).  Conclusion   Preoperative detection of peripheral blood PTX-3 and miR-486-3p levels can be used to predict recurrence and metastasis after laparoscopic radical resection of colorectal cancer,and the combination of the two has higher predictive value.

Key words: laparoscopic radical resection of colorectal cancer, penetrin-3, miR-486-3p, recurrence and metastasis, predictive value