The Value Of Tumor Deposit In The Prediction Of Prognosis In Stage ? Colorectal Cancer Patients

ObjectiveThe definition of tumor deposit(TD)and its significance in the prognosis of patients with colorectal cancer(CRC)have been controversial in different editions of Tumor,Node,Metastasis classification.In addition,there are few studies about the prognostic value of the numbers of TD.The impact of the number of TD on TD-positive stage ? CRC remains obscure.Furthermore,the significance of TD in stage ? CRC still needs further elucidation.Materials and MethodsThis study retrospectively analyzed the clinicopathological data of CRC patients who underwent radical surgical resection in gastrointestinal surgery department of Shandong Provincial Qianfoshan hospital from May 2012 to April 2017.The stages of patient were confirmed as stage ? CRC by postoperative pathology.Data collected included the patient's gender,age,smoking,alcoholism,chronic diseases(including hypertension,coronary heart disease,chronic bronchitis and hepatitis),hemafecia,preoperative serological tumor indicators(carcinoembryonic antigen(CEA):normal range is from 0 to 5.0ng/ml;carbohydrate antigen CA-199:the normal range is 0 to 37 u/ml),operation situation(operating time,blood loss and methods of anastomosis),perioperative blood transfusion,prophylactic stoma,the postoperative complications(anastomotic fistula,bleeding,ileus and wound infection),tumor location,tumor size,T stage,N stage and TNM staging(according to the 8th AJCC/TNM staging system),TD status,the number of the TD,perineural invasion,vascular invasion,number of metastatic lymph nodes,the total number of lymph nodes detection,lymph node positive rate and the condition of postoperative radiation and chemotherapy.Patients who met the inclusion criteria were followed up from the date of radical surgery to May 20,2019.In this study,we analyzed the collected data statistically,patients' survival curve was drawn by kaplan-meier method,differences in survival time were compared by log-rank test,and risk factors affecting patients' survival time were analyzed by univariate and multivariate COX regression models.Receiver-operating characteristic curve(ROC)was used to seek the cut-off value of the number of TD which significantly affects the postoperative survival time of patients.We further analyzed the difference in patients' prognosis and the risk factors that affect patients' prognosis after grouping patients into two groups(number of TD?3 and number of TD<3)according to the threshold.ResultsA total of 235 stage ? CRC patients were involved in this study.TD were found in 44(18.7%)patients,among them,there are 20 patients with TD number?3 and 24 patients with TD number<3.Among all CRC patients,local recurrence occurred in 15 patients who were followed up for 2 years,while 49 patients had distant metastasis.Statistical analysis showed that TD-positive status was associated with local recurrence(P<0.001),but not with other clinicopathological factors.Moreover,TD-positive patients displayed poorer 2-year overall survival(OS)(92.9%vs.79.5%,P=0.004)and 2-year disease-free survival(DFS)(77.9%vs.63.60,P=0.027)than TD-negative patients.Besides,TD-positive status was identified as an independent risk factor for both poor OS(HR=3.749,95%CI=1.596-8.806,P=0.002)and DFS(HR=1.924,95%CI=1.076-3.442,P=0.027).Furthermore,receiver-operating characteristic curve defined 3 TD as the cut-off value for identifying TD-positive patients with poor survival(The AUC of 2-year OS and DFS are 0.802 and 0.827).Patients with?3 TD had much shorter 2-year OS and 2-year DFS than patients with<3 TD(2-year OS:95.8%vs.60.0%,P=0.004;2-year DFS:87.5%vs.35.0%,P<0.001).Patients with TD were divided into 2 groups according the cut-off value of 3 TD.Correlation analyses of the clinicopathological characteristics between the 2 groups found that patients with?3 TD exhibited higher probabilities with poor differentiation(P=0.007),advanced N stage(P=0.001),local recurrence(P=0.025),and distant metastasis postoperatively(P=0.036).After univariate and multivariate analysis,Number of TD?3(HR=6.354,95%CI=1.743-23.161,P=0.005)was discovered as the only independent risk factor for poor DFS in TD-positive patients.ConclusionTD-positive status correlates with local recurrence and implicates poor prognosis in stage ? CRC patients.Besides,number of TD?3 may be a potential factor for predicting shorter survival in TD-positive stage ? CRC patients.However,these results need prospective studies with more samples to validate.