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.
Objectives: The objective of this systematic review is to compare the effectiveness of each operation.
Search strategy: 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.
Selection criteria: We considered RCTs comparing the CW with PPW 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 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.
Main 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.
Authors' 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.