Meta Analysis Of The Impact Of Pericolonic Tumor Deposits On The Prognosis Of Patients With Stage Ⅲ Colorectal Cancer

Objective: Paracolonic tumor deposits(PTDs)were first reported in1935.It has been proved that PTDs are related to the survival and prognosis of colorectal cancer,but they are often confused with the concept of metastatic lymph nodes.This study used meta-analysis method to systematically evaluate the impact of PTDs on the prognosis of patients with stage Ⅲ colorectal cancer and the relationship between PTDs and metastatic lymph nodes of colorectal cancer.Methods: We searched Pub Med,EMBASE,web of science and other international literature databases published before December 31,2020,and CNKI,Wan Fang and other databases about the relationship between PTDs and the prognosis of patients with stage Ⅲ colorectal cancer.The quality of the selected literatures was evaluated according to the quality evaluation scale,and the relevant research data were meta analyzed by Revman 5.3 software.Results: Eight studies involving 18444 patients with stage Ⅲ colorectal cancer were included.Meta analysis showed that the progression free survival rate(OR=0.30,95%CI,0.27-0.32,P<0.00001)and overall survival rate(OR= 0.46,95% CI,0.27-0.79,P = 0.005)of PTDs positive group were lower than that of PTDs negative group.The incidence of neurovascular invasion in PTDs positive group(OR= 1.69,95% CI,1.45-1.97,P < 0.00001)was higher than that in PTDs negative group.At the same time,the difference of overall survival rate between PTDs positive group and lymph node metastasis positive group was small(OR = 1.24,95% CI,1.02-1.50,P = 0.03).The overall survival rate of PTDs positive group was significantly lower than that of PTDs positive and lymph node metastasis positive group(OR = 2.59,95% CI,2.11-3.20,P < 0.00001).Conclusions: In stage Ⅲ colorectal cancer,the presence of PTDs is associated with shorter overall survival and progression free survival,suggesting poorprognosis.PTDs can be used to predict the poor prognosis of colorectalcancer.In stage Ⅲ colorectal cancer,the incidence of neurovascular invasion in patients with PTDs is increased,which indicates that the positive PTDs indicates the increase of biological behavior and malignant degree of tumor.The coexistence of PTDs and lymph node invasion is notsignificant for the prognosis of colorectal cancer.The presence of PTDsalone seems to have prognostic significance similar to that of lymph node invasion alone.The effect of PTDs on the prognosis of patients with stage Ⅲ CRC may be similar to local lymph node metastasis,or between lymph node metastasis and distant metastasis.