Abstract: Objective To analyze and compare the evaluation efficacy of different tumor markers independently and in combination for the outcome of colorectal cancer surgery.Methods This study was a prospective observational study.197 cases of colorectal cancer patients who underwent radical resection in our hospital from January 2021 to February 2023 were selected as the research subjects.According to the clinical outcome within 2 year after surgery,the patients were divided into the group with good clinical outcome and the group with poor clinical outcome.The differences in clinical and disease characteristics,treatment characteristics,and preoperative tumor markers between the two groups of patients were compared.Multivariate logistic regression analysis was used to screen the independent influencing factors related to the poor outcome after radical resection of colorectal cancer patients.The efficacy of different tumor markers independently and in combination in predicting the poor outcome after radical resection of colorectal cancer patients was evaluated and compared through the receiver operating characteristic curve (ROC) and the area under the curve (AUC).Results A total of 197 patients who had undergone radical resection of colorectal cancer and completed at least 2 year of follow-up were finally selected in this study.The age,long diameter of the tumor,proportion of clinical stage Ⅲ,proportion of poor differentiation,operation time,proportion of positive surgical margin,preoperative carcinoembryonic antigen (CEA),carbohydrate antigen 199 (CA199),carbohydrate antigen 242 (CA242),carbohydrate antigen 724 (CA724),human epididymis protein 4 (HE4),count of circulating tumor cells (CTC),and proportion of positive circulating tumor DNA (ctDNA) in the group with poor outcome were all higher than those in the group with good outcome,and the proportion of adenocarcinoma was lower than that in the group with good outcome (all P<0.05).Multivariate logistic regression analysis showed that CEA ,CA199 ,CA242 ,CA724,HE4,CTC count and positive ctDNA  were all risk factors for death after radical resection of colorectal cancer patients (P<0.05).The DeLong test indicated that the area under the curve (AUC) for the combined prediction of CEA,CA199,CA242,CA724,HE4,CTC count,and positive ctDNA was 0.819 (95%CI: 0.718~0.861).This value was higher than the predictive values of each individual tumor marker (Z=3.976,3.856,3.601,3.663,3.525,3.850,3.847,all P<0.05),and at this time,the sensitivity of the combined prediction was 0.823 and the specificity was 0.782.Conclusion Positive CEA,CA199,CA242,CA724,HE4,CTC count,and ctDNA before radical resection of colorectal cancer patients are all risk factors for poor postoperative outcome,and the combined application of the above tumor markers has a higher predictive efficacy.

Key words: colorectal cancer, radical resection, clinical outcome, tumor markers