WITHDRAWN: Pancreaticoduodenectomy (classic Whipple) versus pylorus-preserving pancreaticoduodenectomy (pp Whipple) for surgical treatment of periampullary and pancreatic carcinoma.

backgroundPancreatic 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 operation or a pylorus-preserving pancreaticoduodenectomy. It is unclear which of the procedures is more favourable in terms of survival, mortality, complications and quality of life.

objectivesSeveral publications have highlighted advantages and disadvantages of the two techniques and the current basis of evidence remains unclear. The objective of this systematic review is to compare the effectiveness of each operation. SEARCH STRATEGY: We conducted a search on 28/03/2006 to identify all RCTs, applying no language restriction.We searched the following electronic databases: CENTRAL, CDSR and DARE from The Cochrane Library (2006, issue 2), MEDLINE (1966 to 2006) and EMBASE (1980 to 2006). We handsearched abstracts from 1995 to 2006 from the American Digestive Disease Week (DDW), published in Gastroenterology, and the United European Gastroenterology Week (UEGW), published in Gut. SELECTION CRITERIA: We considered randomised controlled trials comparing the classic Whipple operation with pylorus-preserving pancreaticoduodenectomy to be eligible if they included patients with periampullary or pancreatic carcinoma. DATA COLLECTION AND ANALYSIS: 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 weighted mean differences (WMD), and used hazard ratios (HR) for meta-analysis of survival. Two authors independently evaluated the methodological quality of included studies according to quality standards and by using a questionnaire. MAIN

resultsWe retrieved 1235 abstracts and checked these for eligibility, including seven randomised controlled trials. Our critical appraisal revealed vast heterogeneity with respect to methodological quality and outcome parameters. Our comparisons of 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 (WMD -68.26 minutes; 95% CI -105.70 to -30.83; P = 0.0004) and intra-operative blood loss (WMD -0.76 millilitres; 95% CI -0.96 to -0.56; P < 0.00001) were significantly reduced in the pylorus-preserving pancreaticoduodenectomy group. AUTHORS'

conclusionsThere 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.