Oncologic and Perioperative Outcomes of Different Surgical Approaches for Rectal Cancer: A Systematic Review and Network Meta‑Analysis of Randomized Controlled Trials

Background This study aims to systematically compare the clinical efficacy and safety of four surgical methods: open total mesorectal excision (OpTME), laparoscopic‑assisted total mesorectal excision (LapTME), robotic‑assisted total mesorectal excision (RoTME), and transanal total mesorectal excision (TaTME), to provide evidence-based guidance for clinical decision-making. Methods We conducted a systematic search and a frequentist network meta-analysis of randomized controlled trials (RCTs) up to June 30, 2025 to evaluate the relative efficacy and safety of different surgical methods. Results A total of 19 RCTs involving 6,887 rectal cancer patients were included. Results showed that neither TaTME (hazard ratio [HR]: 1.12, 95% CI: 0.97–1.28) nor RoTME (HR: 1.01, 95% CI: 0.95–1.08) showed no significant improvement over LapTME. Although TaTME (HR: 0.84) and RoTME (HR: 0.71) demonstrated a trend toward reduced overall recurrence rates, the differences were not statistically significant. There were also no significant differences in positive circumferential margin rates among the groups. The OpTME group exhibited a higher risk of postoperative complications (relative risk [RR]: 1.15), while TaTME (RR: 0.97) and RoTME (RR: 0.83) showed a downward trend. Conclusions Current evidence suggests trends favoring TaTME and RoTME for certain efficacy endpoints (e.g., recurrence) and safety outcomes (e.g., postoperative complications), but none of these differences reached statistical significance compared with LapTME. Of note, important outcomes such as anastomotic leak, sphincter preservation, and functional recovery were not assessed due to insufficient data across trials. Therefore, clinical decisions should be based on surgical experience, institutional resources, and patient-specific factors until higher‑quality evidence emerges.