Local Excision Versus Total Mesorectal Excision In Stage I Rectal Cancer: A Meta-analysis Of Randomized Controlled Trials

Background Total mesorectal excision(TME) is the gold standard for stage I rectal cancer. However, it is associated with significant post-operative complications. Local excision(LE) may result in less morbidity and improved quality of life but it is still controversial whether LE can achieve similar oncological outcomes to TME.Objective A systematic review of randomized trials was conducted to compare the oncological and operative outcomes of LE and TME in patients with stage I rectal cancer.Methods Pubmed, Biosis Previews, Science Direct, Ovid and the Cochrane Central Register of Controlled trials were searched. Only randomized trials(RCTs) comparing LE to TME for stage I rectal cancer were included. Two authors independently identified the studies for inclusion and extracted data.The risk of bias was assessed using the Cochrane tool. We analyzed the data with both the fixed effect and the random-effects model meta-analysis.Results 3 RCTs with 210 participants were included. All 3 RCTs compared transanal endoscopic microsurgery(TEM) to TME. Neoadjuvant chemoradiotherapy(CRT) was used in one study. There was no statistical difference in 5-year local recurrence(p=0.48), distant metastasis(p=0.70), overall survival(p=0.44) and cancer specific survival(p=0.71). TEM significantly reduced hospital stay, operative time, blood loss, need for stoma and need for analgesia. Local recurrence was higher in non-downstaged T2 tumors.Conclusions This meta-analysis provides evidence that TEM is oncologically safe in selected stage I rectal cancer. Currently, local excision should be used in the setting of clinical trials. For T2 tumors, downstaging with neoadjuvant CRT is necessary.