Effect of unplanned conversion to open surgery on resection margins and complications in laparoscopic pancreaticoduodenectomy: a systematic review and meta-analysis with meta-regression

Introduction We aimed to investigate the effect of unplanned conversion to open surgery during laparoscopic pancreaticoduodenectomy on resection margins and complications. Methods A systematic review and meta-analysis (proportion and comparison models) with meta-regression using random-effects modelling compliant with PRISMA statement standards was conducted. All studies with a minimum sample size of 15 patients reporting conversion to open surgery in patients undergoing laparoscopic pancreaticoduodenectomy were included. The outcomes included R0 resection, Clavien-Dindo ≥3 complications, and 30-day mortality. Findings A total of 44 studies comprising 6,108 patients were included. Conversion occurred in 11.3% (95% confidence interval (CI) 9.1–13.5). The reason for conversion was bleeding in 27.9% (16.3–39.5%), technical difficulties in 46.5% (95% CI 33.7–59.4), oncological concerns in 29.2% (95% CI 18.2–40.2) and iatrogenic injuries in 7.7% (95% CI 3.4–12.1). Multivariable meta-regression analysis showed that conversion did not affect R0 resection (coefficient: −0.228, p=0.307), Clavien-Dindo ≥3 complications (coefficient: 0.129, p=0.609) and 30-day mortality (coefficient: −0.013, p=0.647). The outcomes were not affected by the reasons for conversion. Comparison meta-analysis showed that conversion does not affect R0 resection (risk difference (RD): −0.07, 95% CI −0.17–0.03, p=0.18), Clavien-Dindo ≥3 complications (odds ratio: 2.17, 95% CI 0.67–6.99, p=0.20) and 30-day mortality (RD: 0.02, 95% CI −0.04–0.07, p=0.57). Conclusions Unplanned conversion to open surgery, regardless of the reason for conversion, may not affect resection margins and complications in laparoscopic pancreaticoduodenectomy (moderate certainty). Conversion during laparoscopic pancreaticoduodenectomy should not be seen as a failure because it has no negative impact on outcomes; however, not converting when indicated will undoubtedly have negative impact.