title: Minimally Invasive Versus Open Pancreatoduodenectomy: Systematic Review and Meta-analysis of Comparative Cohort and Registry Studies.
abstract: OBJECTIVE
  This study aimed to appraise and to evaluate the current evidence on minimally invasive pancreatoduodenectomy (MIPD) versus open pancreatoduodenectomy only in comparative cohort and registry studies.
  
  
  BACKGROUND
  Outcomes after MIPD seem promising, but most data come from single-center, noncomparative series.
  
  
  METHODS
  Comparative cohort and registry studies on MIPD versus open pancreatoduodenectomy published before August 23, 2015 were identified systematically and meta-analyses were performed. Primary endpoints were mortality and International Study Group on Pancreatic Fistula grade B/C postoperative pancreatic fistula (POPF).
  
  
  RESULTS
  After screening 2293 studies, 19 comparative cohort studies (1833 patients) with moderate methodological quality and 2 original registry studies (19,996 patients) were included. For cohort studies, the median annual hospital MIPD volume was 14. Selection bias was present for cancer diagnosis. No differences were found in mortality [odds ratio (OR) = 1.1, 95% confidence interval (CI) = 0.6-1.9] or POPF [(OR) = 1.0, 95% CI = 0.8 to 1.3]. Publication bias was present for POPF. MIPD was associated with prolonged operative times [weighted mean difference (WMD) = 74 minutes, 95% CI = 29-118], but lower intraoperative blood loss (WMD = -385 mL, 95% CI = -616 to -154), less delayed gastric emptying (OR = 0.6, 95% = CI 0.5-0.8), and shorter hospital stay (WMD = -3 days, 95% CI = -5 to -2). For registry studies, the median annual hospital MIPD volume was 2.5. Mortality after MIPD was increased in low-volume hospitals (7.5% vs 3.4%; P = 0.003).
  
  
  CONCLUSIONS
  Outcomes after MIPD seem promising in comparative cohort studies, despite the presence of bias, whereas registry studies report higher mortality in low-volume centers. The introduction of MIPD should be closely monitored and probably done only within structured training programs in high-volume centers.
authors: *Department of Surgery, Academic Medical Center, Academic Medical Center, Amsterdam, The Netherlands†Department of Surgery, Onze Lieve Vrouwe Gasthuis, Academic Medical Center, Amsterdam, The Netherlands‡Clinical Research Unit, Academic Medical Center, Amsterdam, The Netherlands§Department of Surgery, Jeroen Bosch Hospital, Den Bosch, The Netherlands.
authors: Thijs
authors: T
authors: de Rooij
authors: Martijn Z
authors: MZ
authors: Lu
authors: M Willemijn
authors: MW
authors: Steen
authors: Michael F
authors: MF
authors: Gerhards
authors: Marcel G
authors: MG
authors: Dijkgraaf
authors: Olivier R
authors: OR
authors: Busch
authors: Daan J
authors: DJ
authors: Lips
authors: Sebastiaan
authors: S
authors: Festen
authors: Marc G
authors: MG
authors: Besselink
mesh_terms: D015331:Cohort Studies; D006801:Humans; D010535:Laparoscopy; D010190:Pancreatic Neoplasms / Q000601:surgery; D016577:Pancreaticoduodenectomy; D018579:Patient Selection; D012042:Registries