Comparison of short-term surgical outcomes and long-term survival between emergency and elective surgery for colorectal cancer: A systematic review and meta-analysis

Abstract Objective: The objective of this study was to summarize relevant data from previous reports and perform a meta-analysis to compare short-term surgical outcomes and long-term oncological outcomes between emergency and elective surgery for colorectal cancer(CRC). Methods: A systematic literature search was performed using PubMed and Embase databases and relevant data were extracted. Postoperative morbidity, hospital mortality within 30 days, postoperative recovery, overall survival(OS) and relapse-free survival(RFS) were compared using a fixed or random-effect model. Results: 28 studies involving 353,686 participants were enrolled for this systematic review and meta-analysis, and 23.5%(83,054/353,686) of CRC patients underwent emergency surgery. The incidence of emergency presentations in CRC patients ranged from 2.7% to 38.8%. Lymph node yield of emergency surgery was comparable to that of elective surgery(WMD:0.70, 95%CI:-0.74,2.14, P=0.340; I 2 =80.6%). Emergency surgery had a higher risk of postoperative complications(OR:1.83, 95%CI:1.62-2.07, P<0.001; I 2 =10.6%) and hospital mortality within 30 days(OR:4.62, 95%CI:4.18-5.10, P<0.001; I 2 =42.9%) than elective surgery for CRC. In terms of long-term oncological outcomes, emergency surgery was significantly associated with poorer RFS (HR: 1.51, 95%CI:1.24-1.83, P<0.001; I 2 =58.9%) and OS(HR:1.60, 95%CI: 1.47-1.73, P<0.001; I 2 =63.4%) of CRC patients. In addition, the subgroup analysis for colon cancer patients revealed a pooled HR of 1.73 for OS(95% CI:1.52-1.96, P<0.001), without the evidence of significant heterogeneity(I 2 =21.2%). Conclusion: Emergency surgery for CRC had an adverse impact on short-term surgical outcomes and long-term survival. A focus on early screening programs and health education were warranted to reduce emergency presentations of CRC patients.