Comparing perioperative and oncological outcomes of transanal and laparoscopic total mesorectal excision for rectal cancer: a meta-analysis of randomized controlled trials and prospective studies.

INTRODUCTION: Meta-analysis of the results of transanal total mesorectal excision (taTME) and laparoscopic TME (laTME) regarding perioperative and oncological outcomes have been conducted. Due to the lack of high-quality randomized controlled trials (RCTs) and prospective studies in the included literature, the conclusions are unreliable. This study included RCTs and prospective studies for analysis to obtain more reliable conclusions.

MATERIALS AND METHODS: Systematic searches of the PubMed, Embase, and Cochrane Library databases were conducted up to June 2023. To assess the quality, the Cochrane quality assessment tool and the Newcastle-Ottawa Scale were employed. The perioperative and oncological outcomes were then analyzed. The I2 statistic was used to evaluate statistical heterogeneity and sensitivity analyses was conducted.

RESULTS: A total of 22 studies, comprising 5056 patients, were included in the analysis, of which 6 were RCTs and 16 were prospective studies. The conversion rate in the taTME group was significantly lower than that in the laTME group (OR 0.14, 95% CI 0.09 to 0.22, P < 0.01), and the circumferential resection margin (CRM) was longer (MD 0.99 mm, 95% CI 0.66 to 1.32 mm, P < 0.01), with a lower rate of positive CRM involvement (OR 0.68, 95% CI 0.47 to 0.97, P = 0.03). No statistically significant differences were found in terms of the operation time, intraoperative blood loss, complications, anastomotic leakage, uroschesis, obstruction, secondary operation, hospital stay, urethral injury, readmission, mortality rate within 30 days, mesorectal resection quality, number of harvested lymph nodes, distal resection margin (DRM), positive DRM, local recurrence, and distance recurrence (P > 0.05).

CONCLUSION: According to the findings of this meta-analysis, which is based on RCTs and prospective studies, taTME appears to have an advantage over laTME in terms of conversion rate and CRM involvement.