Background: Minimally invasive surgery (MIS) has obtained increasing popularity, mainly the laparoscopic and robotic approaches, for the treatment of gastrointestinal (GI) malignancies. Nevertheless, it is still controversial whether such surgeries are equally effective for advanced GI cancers as conventional open surgeries.

Objective: To assess perioperative and oncological outcomes after minimally invasive surgery (MIS) or open surgery for advanced gastrointestinal cancers and to compare the two approaches.

Methods: By conducting a thorough literature search in PubMed, PMC and other major databases, we identified studies in which the authors had compared MIS and open surgery for advanced gastric and colorectal cancers. Odds ratios (OR) with 95% confidence intervals (CI) were combined using the random effects models. The extent of variation due to heterogeneity was determined using the I² statistics.

Results: Various studies, including randomized controlled trials and observational cohorts, were analyzed for this meta-analysis. MIS resulted in a significantly reduction of postoperative complications and comparable oncologic outcomes. For anastomotic leak, the combined OR was 0.56 (95% CI: 0.29-1.07) favouring MIS, with very low heterogeneity (I² = 7%). The results of gastric and colorectal cancers were similar in the subgroup analysis.

Conclusion: When performed in highly experienced centers, MIS offers comparable oncological safety and superior perioperative outcomes compared with open surgery in patients with advanced GI cancers.