Radical versus local surgical excision for early rectal cancer: A systematic review and meta-analysis.

3622 Background: Colorectal cancer is the third common cancer worldwide. Radical excision (RE) as total mesorectal excision for rectal cancer carries a higher risk of mortality and morbidity, while local excision (LE) could decrease these postoperative risks. However, the long-term oncologic outcomes of LE are still debatable. We aim to study the effect of LE versus RE in T1 and T2 rectal cancer. Methods: We conducted a systematic review and meta-analysis. We searched PubMed and CENTRAL databases, using an optimized search-strategy from inception until 15 June 2021, without restriction on publication date or status. We included only cohort and randomized controlled trials (RCTs). Two authors independently screened the title, abstracts, and full-text manuscripts for inclusion and data extraction. All included trials contained at least one of the primary outcomes. We used RevMan 5.4 tool for data analysis. We calculated both hazards ratio (HR) and risk ratio (RR) for the 5-years survival analyses, with their 95% confidence intervals (CI). We assessed both clinical and statistical heterogeneity of the studies; I 2 >75% was considered highly heterogeneous. We used random effect model (REM). We used standardized mean difference (SMD) for hospitalization days. We conducted a subgroup analysis of patients with T1-only without adjuvant chemo/radiotherapy (CRT). Results: We retrieved from the search a total of 1243 reports. A total of 18 studies were included for final meta-analysis (4 RCTs and 14 retrospective cohorts). Nine studies were multi-central while ten were unicentral studies. We did not find any difference in risk ratio (RR) between overall survival (OVS) and disease-free survival (DFS). But there were higher HRs in OVS and DFS with LE as compared to RE. A higher recurrence rate was also seen with LE. Six studies showed absent 30-days postoperative mortality in both groups so we used peto-odds ratio. Postoperative mortality and morbidity were lower with LE rather than RE. Conclusions: LE for early stage rectal cancer has a higher risk of decreased 5-year OVS and DFS than RE, with higher local recurrence rate. However, LE is associated with lower early postoperative mortality, morbidity, and hospitalization days, as compared to RE. Patient selection is key to balance these risks for the optimal outcome. [Table: see text]