Short- and long-term outcomes of minimally invasive vs. open pelvic exenteration in rectal tumours: a focused meta-analysis

Purpose: Pelvic exenteration (PE) is a complex surgical procedure used to treat patients with recurrent or locally advanced rectal cancer (LARC) as a final recourse. Thus, minimally invasive surgery (MIS) has emerged as an alternative to the traditional open PE as it may reduce surgical trauma and improve recovery. This meta-analysis compared the clinical outcomes between MIS and open PE in patients with LARC. Methods: A systematic review and meta-analysis were conducted following PRISMA and AMSTAR guidelines. Six retrospective studies comprising 368 patients (179 MIS patients; 189 open patients) were included. Data on operative parameters along with short-term and long-term outcomes, including the 3-year overall (OS) and disease-free survival (DFS), were extracted. Risk ratios (RRs) and odds ratios (ORs) were calculated for binary outcomes, while standardised mean differences (SMDs) were calculated for continuous outcomes. All measures were reported with 95% confidence intervals (CIs) using random-effects models. Results: MIS was associated with significantly reduced blood loss (standardised mean difference (SMD), − 1.57; 95% CI, − 2.27 to − 0.88; p < 0.00001), shorter hospital stays (SMD, − 6.46; 95% CI, − 12.21 to − 0.71; p = 0.03), and quicker diet resumption (SMD: − 0.79; 95% CI, − 1.36 to − 0.21; p = 0.008) than open PE. MIS was associated with a borderline reduction in total complications (OR, 0.45; 95% CI, 0.20–1.00; p = 0.05) and lower rates of abdominal wound complications (OR, 0.22; 95% CI, 0.11 to 0.45; p < 0.0001). No significant differences were observed in R0 resection rates, major complications, or mortality. For long-term outcomes, MIS demonstrated significantly improved 3-year OS (RR, 1.19; 95% CI, 1.01 to 1.41; p = 0.04), whereas 3-year DFS showed no significant difference (RR, 1.02; 95% CI, 0.79 to 1.41; p = 0.87). Conclusion: MIS offers significant short-term advantages over open PE, including reduced blood loss, faster recovery, and fewer complications while demonstrating improved 3-year OS. These findings support MIS PE as a safe, effective, and viable option for patients with recurrent or LARC.