| Objective:Currently,there is still controversy about the choice of primary cancer management in asymptomatic colorectal cancer patients with unresectable metastases.Meta-analysis was conducted to evaluate the clinical prognosis and safety of primary cancer resection(PTR)in patients with unresectable metastases and asymptomatic primary colorectal cancer.So as to provide some theoretical basis for clinicians to choose the best treatment plan.Methods:Literature related to primary resection and systemic chemotherapy in the treatment of unresectable metastases and asymptomatic primary colorectal cancer was retrieved from PubMed,Embase,Cochrane Library,CNKI and WanFang database from its establishment to September 2020.Literature screening and data extraction were conducted by 2 surgeons independently.Non-randomized controlled trials(NRCTs)were included to evaluate the quality of the literature using the Newcastle Ottawa Scale(NOS),and randomized controlled trials(RCTs)were evaluated using the risk of bias assessment tool.STATA15.1 software was used for Meta analysis.The odds ratio(OR)and 95%confidence interval(95%CI)were used for 1-year,2-year,and 5-year survival and risk of death.Median survival time was measured by mean difference(MD)and 95%CI.Single rate data(R)and 95%CI indicated that R=OR value ×100%.12 was used to analyze the heterogeneity.I2≤50%was considered as no significant heterogeneity,and fixed effect model(FEM)was used,otherwise random effect model(REM)was used for analysis.The stability of the results was checked by sensitivity analysis.The publication bias was evaluated by the symmetry of funnel plot and verified by Egger’s method.Results:In the end,a total of 28 literatures were included in the study,26 were retrospective cohort studies and 2 were randomized controlled trials,with a total sample size of 214,342 cases,including 122,759 cases in the initial primary resection group and 91,583 cases in the initial systemic treatment group.Results of the Meta-analysis showed that the median survival time in the initial PTR group was 8.87 months longer than that in the systemic chemotherapy group(MD=8.87,95%CI:8.86～8.88,P<0.0001).The risk of tumor progression or death in the resection group was only 62%of that in the chemotherapy group(95%CI:0.52～0.73).The 1-year survival rate in the primary resection group was higher(OR=1.35,95%CI:1.01～1.35).The 2-year survival rate was higher(OR=2.01,95%CI:1.78～2.28).The 5-year survival rate was higher(OR=3.25;95%CI:2.29～4.60);The total postoperative complication rate in the initial primary resection group was 22%(95%CI:0.13～0.30),the incidence of incision infection was 4%(95%CI:0.03～0.05);Urinary tract infections were 2%(95%CI:0.01～0.03);Anastomotic fistula was 2%(95%CI:0.01～0.03);The total complication rate in the systemic chemotherapy group was 20%(95%CI:0.10～0.29).The rate of emergency surgery was 14%(95%CI:0.08～0.20).Conclusion:For patients with unresectable metastatic colorectal cancer and asymptomatic primary colorectal cancer,initial primary resection can significantly prolong the median survival time of patients and improve the overall survival rate of patients.Therefore,initial primary resection is recommended for patients,but individualized treatment is required for different patients.The total complication rate in the group undergoing primary resection was 22%,but the occurrence of fatal complications was lower,so surgical resection of the primary lesion was safe and feasible.The complication rate was 20%in patients with initial systemic treatment and 14%in patients with emergency surgery,and since the majority of patients will not undergo emergency surgery for the primary tumor,initial chemotherapy is also safe. |
