Correlation Between Preoperative Immune Index Measured Based On Blood And The Prognosis Of Colorectal Cancer

Objective: The immunity of colorectal cancer patients is closely related to occurrence and progression of tumor.Thus,the present study aims to explore the correlation between blood indexes of immune function(including preoperative immunoglobulin IgG,IgA,IgM and CD4+ T lymphocyte count,CD8+ T lymphocyte count,ratio of CD4+/CD8+ T lymphocyte)and prognosis,as well as pathological characteristics of colorectal cancer.And based on the above investigation,we could evaluate the clinical significance and potential application value of preoperative blood immune function related indicators in colorectal cancer patients.Methods: The clinical data of colorectal cancer patients and benign control(hemorrhoids,colonic polyp,et al)were collected who admitted to department of colorectal and anal surgery,the First Affiliated Hospital of Guangxi Medical University from January 2014 to December 2014.Clinical data of colorectal cancer patients included general information,detection results of blood immune function related indicators(IgG,IgA,IgM content and CD4+ T lymphocyte count,CD8+ T lymphocyte count,ratio of CD4+/CD8+ T lymphocyte),the pathological diagnosis of colorectal cancer and the postoperative survival time.Statistical analysis was utilized to evaluate the level of immune function related indicators between colorectal cancer patients and benign diseases patients.Moreover,the comparison of immune function related indicators was performed in different clinicopathologic characteristics.In the survival analysis,Kaplan-Meier and log rank test were conducted.Univariate and multivariate COX regression analysis were utilized to assess the relationship between immune function related indicators and prognosis of colorectal cancer patients.Meanwhile,nomogram based on immune function related indicators was conducted to predict the prognosis of colorectal cancer and time dependent receiver operator characteristic(ROC)curve was conducted to appraise the efficiency of nomogram,thereby evaluating the clinical application value of preoperative blood immune indicators for colorectal cancer.Results: 1.Compared with benign diseases patients,the level of IgG(10.06±2.47g/L vs 12.08±3.18g/L,P<0.001),IgA(2.43±1.29g/L vs 2.80±0.96g/L,P=0.002)and CD8+ T lymphocyte absolute count(508.87±296.56 vs599.30±269.69 cell/u L,P=0.006)were relatively lower in colorectal cancer patients.No significant difference of the level of IgM,CD4+ T lymphocyte count and ratio of CD4+/CD8+ T lymphocyte was observed between colorectal cancer patients and benign controls.2.The present study showed CD4+ T lymphocyte count was correlated with age(P=0.048),CEA(P=0.038),and lymph node metastasis(P=0.022)in colorectal patients.CD8+ T lymphocyte count was also relevant to CEA level(P=0.028)and lymph node metastasis(P=0.016).No statistical significance was observed between the rest clinicopathologic features and CD4+,CD8+ T lymphocyte count(all P>0.05).Only serum IgM level was correlated with lymph node metastasis of colorectal cancer(P=0.007).IgG and IgA were not reached significant difference in various group of clinicopathologic characteristics of colorectal cancer(all P>0.05).3.The univariate COX analysis revealed CEA(HR=2.816,95%CI:1.295-6.121,P=0.009),N stage(HR=2.751,95%CI: 1.267-5.975,P=0.011),IgA level(HR=0.061,95%CI: 0.012-0.307,P=0.001)and CD8+ T lymphocyte(HR=0.319,95%CI: 0.140-0.726,P=0.006)were relevant to the prognosis of colorectal cancer.Subsequently,multivariate COX analysis revealed that IgA level(HR=0.143,95%CI: 0.028-0.738,P=0.020)and CD8+ T lymphocyte count(HR=0.395,95%CI: 0.171-0.915,P=0.030)could predict the survival of colorectal cancer independently.Nomogram model based on IgA level and CD8+ T lymphocyte count was performed to predict the survival of colorectal cancer and the AUC of time dependent ROC reached 0.8,which indicated well discrimination of the nomogram model.Conclusion: The preoperative blood immune status is relevant to the progression and prognosis of colorectal cancer.Meanwhile,preoperative level of IgA and CD8+ T lymphocyte in blood own a certain predictive value for postoperative survival of colorectal cancer,thereby supporting the immunotherapy for colorectal cancer.Thus,IgA level and CD8+ T lymphocyte count are virtually worth to perform further investigation in order to evaluate its value of clinical application for colorectal cancer.