title: Pylorus-preserving pancreaticoduodenectomy (pp Whipple) versus pancreaticoduodenectomy (classic Whipple) for surgical treatment of periampullary and pancreatic carcinoma.
abstract: BACKGROUND
  Pancreatic cancer is the fourth leading cause of cancer death for men and the fifth for women. The standard treatment for resectable tumours is either a classic Whipple (CW) operation or a pylorus-preserving pancreaticoduodenectomy (PPW). It is unclear which of the procedures is more favourable in terms of survival, mortality, complications and quality of life.
  
  
  OBJECTIVE
  The objective of this systematic review is to compare the effectiveness of each operation.
  
  
  METHODS
  We conducted searches on 28 March 2006 and 11 January 2011 to identify all randomised controlled trials (RCTs), applying no language restrictions. We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL), CDSR and DARE from The Cochrane Library (2010, Issue 4), MEDLINE (1966 to January 2011), and EMBASE (1980 to January 2011). Abstracts from Digestive Disease Week and U nited European Gastroenterology Week (1995 to 2010). No additional studies were indentified upon updating the systematic review in 2011.
  
  
  METHODS
  We considered RCTs comparing the CW with PPW to be eligible if they included patients with periampullary or pancreatic carcinoma.
  
  
  METHODS
  Two authors independently extracted data from the included studies. We used a random-effects model for pooling data. We compared binary outcomes using odds ratios (OR), pooled continuous outcomes using mean differences (MD) and used hazard ratios (HR) for meta-analysis of survival. Two authors independently evaluated the methodological quality and risk of bias of the included studies according to Cochrane standards.
  
  
  RESULTS
  We included six randomised controlled trials with a total of 465 patients. Our critical appraisal revealed vast heterogeneity with respect to methodological quality and outcome parameters. In-hospital mortality (OR 0.49; 95% confidence interval (CI) 0.17 to 1.40; P = 0.18), overall survival (HR 0.84; 95% CI 0.61 to 1.16; P = 0.29) and morbidity showed no significant differences. However, we noted that operating time (MD -68.26 minutes; 95% CI -105.70 to -30.83; P = 0.0004) and intra-operative blood loss (MD -0.76 millilitres; 95% CI -0.96 to -0.56; P < 0.00001) were significantly reduced in the PPW group. All significant results have low quality of evidence based on GRADE criteria.
  
  
  CONCLUSIONS
  There is no evidence of relevant differences in mortality, morbidity and survival between the two operations. Given obvious clinical and methodological heterogeneity, future research must be undertaken to perform high-quality randomised controlled trials of complex surgical interventions on the basis of well-defined outcome parameters.
authors.affiliation: Department of General, Visceral and Transplant Surgery, University of Heidelberg, Im Neuenheimer Feld 10, Heidelberg, Germany, 69120.
authors.forename: Markus K
authors.initials: MK
authors.lastname: Diener
authors.forename: Christina
authors.initials: C
authors.lastname: Fitzmaurice
authors.forename: Guido
authors.initials: G
authors.lastname: Schwarzer
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Seiler
authors.forename: Gerd
authors.initials: G
authors.lastname: Antes
authors.forename: Hanns-Peter
authors.initials: HP
authors.lastname: Knaebel
authors.forename: Markus W
authors.initials: MW
authors.lastname: Büchler
mesh_terms: D014670:Ampulla of Vater / Q000601:surgery*; D003138:Common Bile Duct Neoplasms / Q000401:mortality / Q000601:surgery*; D005746:Gastric Emptying; D006801:Humans; D010185:Pancreatic Fistula / Q000209:etiology; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000601:surgery*; D016577:Pancreaticoduodenectomy / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D011708:Pylorus / Q000601:surgery*; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic