Short-term and Long-term Efficacy in Robot-assisted Laparoscopic Treatment for Mid and Low Rectal Cancer: A systematic review and meta-analysis
Authors: Wu Huiming , Guo Renkai , Li Huiyu 
Published: October 2023

Abstract
Objective
This study aims to conduct a meta-analysis to evaluate the short-term and long-term therapeutic effects of robot-assisted laparoscopic treatment in patients with mid and low rectal cancer.
Methods
A comprehensive search strategy was employed to retrieve relevant literature from PubMed, NCBI, Medline, and Springer databases, spanning the database inception until August 2023. The focus of this systematic review was on controlled studies that compared the treatment outcomes of robot-assisted laparoscopy (Rob) and conventional laparoscopy (Lap) in the context of mid and low rectal cancer. Data extraction and literature review were meticulously conducted by two independent researchers(HMW; RKG). The synthesized data underwent rigorous analysis utilizing Revman 5.4 software, adhering to established methodological standards in systematic reviews. The primary outcomes encompass perioperative outcomes and oncological outcomes. Secondary outcomes include long-term outcomes
Result
A total of 11 studies involving 2,239 patients with mid and low rectal cancer were included—comprising 3 randomized controlled trials (RCTs) and 8 retrospective analyses (NRCTs); the Rob group consisted of 1,111 cases, while the Lap group included 1,128 cases. There were no significant differences between the two groups in terms of operation time (MD = 11.10, 95% CI: -16.12 to 38.32, P = 0.42). The Rob group exhibited less intraoperative bleeding (MD=-40.01, 95% CI: -57.61 to -22.42, P < 0.00001). The occurrence rates of protective stoma showed no significant differences between the groups (OR = 0.95, 95% CI: 0.65 to 1.39, P = 0.81). The Rob group had a lower rate of conversion to open surgery (OR = 0.27, 95% CI: 0.09 to 0.82, P = 0.02). The Rob group had a higher number of harvested lymph nodes (MD = 1.97, 95% CI: 0.77 to 3.18, P = 0.001). There were no significant differences between the two groups in terms of proximal resection margin distance (MD=-0.08, 95% CI: -1.72 to 1.56, P = 0.92) and distal resection margin distance (MD = 0.16, 95% CI: -0.10 to 0.43, P = 0.23). The Rob group had a lower circumferential resection margin positive rate (OR = 0.46, 95% CI: 0.23 to 0.95, P = 0.04). There were no significant differences in time to flatus (SMD=-0.20, 95% CI: -0.49 to -0.09, P = 0.18), time to liquid diet (SMD=-0.11, 95% CI: -0.57 to 0.36, P = 0.65), and total hospital stay (MD=-0.30, 95% CI: -0.92 to 0.32, P = 0.35) between the two groups. In terms of postoperative morbidity rate, the Rob group had a lower occurrence (OR = 0.66, 95% CI: 0.53 to 0.82, P < 0.0001), and the occurrence rate of complications with Clavien–Dindo grade ≥ 3 was lower (OR = 0.60, 95% CI: 0.39 to 0.90, P = 0.02). Subgroup analysis for postoperative morbidity revealed a lower anastomotic leakage rate in the Rob group (OR = 0.66, 95% CI: 0.45 to 0.97, P = 0.04), with no significant differences in abdominal or anastomotic bleeding (OR = 0.65, 95% CI: 0.32 to 1.31, P = 0.23), wound-related complications (OR = 0.66, 95% CI: 0.39 to 1.11, P = 0.12), ileus (OR = 0.54, 95% CI: 0.26 to 1.13, P = 0.10), urinary retention or infection (OR = 0.58, 95% CI: 0.32 to 1.05, P = 0.07), stoma-related complications (OR = 0.86, 95% CI: 0.40 to 1.85, P = 0.70), and pulmonary infection (OR = 0.60, 95% CI: 0.19 to 1.85, P = 0.37).There were no significant differences between the two groups in terms of 3 years overall survival rate (MD = 1.15, 95% CI: 0.60 to 2.22, P = 0.67) and 3 years disease-free survival rate (MD = 1.23, 95% CI: 0.74 to 2.03, P = 0.42).
Conclusion
Robot-assisted laparoscopic treatment for mid and low rectal cancer yields favorable outcomes, demonstrating both efficacy and safety. In comparison to conventional laparoscopy, patients experience reduced intraoperative bleeding and a lower incidence of complications. Notably, the method achieves comparable short-term and long-term treatment results to those of conventional laparoscopic surgery, thus justifying its consideration for widespread clinical application.