Neoadjuvant Chemotherapy For Patients With Resectable Colorectal Cancer Liver Metastases:A Systematic Review And Meta-analysis

Objective: Data processing was performed on the literature about neoadjuvant chemotherapy in patients with resectable liver metastasis of colorectal cancer published in the database using software such as Stata and Review Manger.And meanwhile to evaluate the clinical efficacy and safety of patients with liver metastases from colorectal cancer who received neoadjuvant chemotherapy compared with those who did not receive neoadjuvant chemotherapy.Methods: We searched Pub Med,Embase,Web of Science,the Cochrane Library,Chinese Biomedical Literature Database(CBM)and Wanfang Database from inception to December,2020 to collect clinical studies comparing NAC with non-NAC.Data processing and statistical analyses were performed using Stata V.15.0 and Review Manager 5.0 software.Control studies that met the requirements were included.The study indicators included 5-year overall survival,5-year disease-free survival,duration of operation,blood loss,length of hospital stay,the number of liver metastases,the Synchronous liver metastases,perioperative complications,bile leakage,surgical site infection,liver failure,and blood transfusions,major liver resection and R0 resection margin.Results: Finally,32 studies involving 11236 patients were included in this analysis.We divided the patients into two groups,the NAC group(that received neoadjuvant chemotherapy:n =4791)and the non-NAC group(that received no neoadjuvant chemotherapy:n =6445).The meta-analysis outcome showed a statistically significant difference in the 5-year overall survival(OS)and 5-year disease-free survival(DFS)between the two groups.The hazard ratio(HR)and 95% confidence interval(CI)were HR = 0.49,95% CI = 0.39–0.61 P < 0.01 and HR = 0.48 95% CI = 0.36–0.63 P <0.01.The duration of surgery in the NAC group was longer than of the non-NAC group(SMD = 0.41,95% CI = 0.01–0.82,P< 0.05).The meta-analysis showed that neoadjuvant chemotherapy did not affect the incidence of postoperative complications [OR=1.00,95%CI=0.76-1.31,P=0.989].Conclusion: We found that NAC could improve the long-term prognosis of patients with resectable colorectal liver metastases.Meanwhile,NAC may not increase complications such as postoperative biliary leakage,surgical site infection and liver failure.