title: The pylorus: take it or leave it? Systematic review and meta-analysis of pylorus-preserving versus standard whipple pancreaticoduodenectomy for pancreatic or periampullary cancer.
abstract: BACKGROUND
  Our objective was to determine the relative effects of pylorus-preserving pancreaticoduodenectomy (PPPD) and standard Whipple pancreaticoduodenectomy (SWPD) in patients with pancreatic or periampullary cancer.
  
  
  METHODS
  We searched seven bibliographic databases, conference proceedings, and reference lists of articles and textbooks, and we contacted experts in the field of hepatobiliary surgery. We included published and unpublished randomized controlled trials. We evaluated the methodological quality of trials and, in duplicate, extracted data regarding operative, perioperative, and long-term outcomes. We contacted all authors and asked them to provide additional information regarding the trials. We pooled results from the studies by using a random-effects model, evaluated the degree of heterogeneity, and explored potential explanations for heterogeneity.
  
  
  RESULTS
  Six trials that included a total of 574 patients met eligibility criteria. In the pooled analysis, PPPD was 72 minutes faster (P < .001, 95% confidence interval [95% CI], 53-92), with 284 mL less blood loss (P < .001, 95% CI, 176-391) and .66 fewer units of blood transfused (P = .002, 95% CI, .25-1.16). Other perioperative and long-term outcomes did not statistically differ, although the confidence intervals include important differences.
  
  
  CONCLUSIONS
  Moderate-quality evidence suggests PPPD is a faster procedure with less blood loss compared with SWPD. Large absolute differences in other key outcomes are unlikely; excluding relatively small differences will, however, require larger, methodologically stronger trials.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main St. W, Hamilton, Ontario, L85 3Z5, Canada. pjkarani@uwo.ca
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Karanicolas
authors.forename: Edward
authors.initials: E
authors.lastname: Davies
authors.forename: Regina
authors.initials: R
authors.lastname: Kunz
authors.forename: Matthias
authors.initials: M
authors.lastname: Briel
authors.forename: H Pavan
authors.initials: HP
authors.lastname: Koka
authors.forename: Darrin M
authors.initials: DM
authors.lastname: Payne
authors.forename: Shona E
authors.initials: SE
authors.lastname: Smith
authors.forename: Hui-Ping
authors.initials: HP
authors.lastname: Hsu
authors.forename: Pin-Wen
authors.initials: PW
authors.lastname: Lin
authors.forename: Christian
authors.initials: C
authors.lastname: Bloechle
authors.forename: Karl-Joseph
authors.initials: KJ
authors.lastname: Paquet
authors.forename: Gordon H
authors.initials: GH
authors.lastname: Guyatt
mesh_terms: D014670:Ampulla of Vater / Q000601:surgery*; D016063:Blood Loss, Surgical; D001803:Blood Transfusion; D003138:Common Bile Duct Neoplasms / Q000601:surgery*; D019992:Databases as Topic; D006801:Humans; D008137:Longitudinal Studies; D015233:Models, Statistical; D010190:Pancreatic Neoplasms / Q000601:surgery*; D016577:Pancreaticoduodenectomy / Q000379:methods*; D011708:Pylorus / Q000601:surgery*; D016032:Randomized Controlled Trials as Topic; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome