title: Laparoscopic versus open distal pancreatectomy for pancreatic cancer.
abstract: BACKGROUND
  Surgical resection is currently the only treatment with the potential for long-term survival and cure of pancreatic cancer. Surgical resection is provided as distal pancreatectomy for cancers of the body and tail of the pancreas. It can be performed by laparoscopic or open surgery. In operations on other organs, laparoscopic surgery has been shown to reduce complications and length of hospital stay as compared with open surgery. However, concerns remain about the safety of laparoscopic distal pancreatectomy compared with open distal pancreatectomy in terms of postoperative complications and oncological clearance.
  
  
  OBJECTIVE
  To assess the benefits and harms of laparoscopic distal pancreatectomy versus open distal pancreatectomy for people undergoing distal pancreatectomy for pancreatic ductal adenocarcinoma of the body or tail of the pancreas, or both.
  
  
  METHODS
  We used search strategies to search the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded and trials registers until June 2015 to identify randomised controlled trials (RCTs) and non-randomised studies. We also searched the reference lists of included trials to identify additional studies.
  
  
  METHODS
  We considered for inclusion in the review RCTs and non-randomised studies comparing laparoscopic versus open distal pancreatectomy in patients with resectable pancreatic cancer, irrespective of language, blinding or publication status..
  
  
  METHODS
  Two review authors independently identified trials and independently extracted data. We calculated odds ratios (ORs), mean differences (MDs) or hazard ratios (HRs) along with 95% confidence intervals (CIs) using both fixed-effect and random-effects models with RevMan 5 on the basis of intention-to-treat analysis when possible.
  
  
  RESULTS
  We found no RCTs on this topic. We included in this review 12 non-randomised studies that compared laparoscopic versus open distal pancreatectomy (1576 participants: 394 underwent laparoscopic distal pancreatectomy and 1182 underwent open distal pancreatectomy); 11 studies (1506 participants: 353 undergoing laparoscopic distal pancreatectomy and 1153 undergoing open distal pancreatectomy) provided information for one or more outcomes. All of these studies were retrospective cohort-like studies or case-control studies. Most were at unclear or high risk of bias, and the overall quality of evidence was very low for all reported outcomes.Differences in short-term mortality (laparoscopic group: 1/329 (adjusted proportion based on meta-analysis estimate: 0.5%) vs open group: 11/1122 (1%); OR 0.48, 95% CI 0.11 to 2.17; 1451 participants; nine studies; I(2) = 0%), long-term mortality (HR 0.96, 95% CI 0.82 to 1.12; 277 participants; three studies; I(2) = 0%), proportion of people with serious adverse events (laparoscopic group: 7/89 (adjusted proportion: 8.8%) vs open group: 6/117 (5.1%); OR 1.79, 95% CI 0.53 to 6.06; 206 participants; three studies; I(2) = 0%), proportion of people with a clinically significant pancreatic fistula (laparoscopic group: 9/109 (adjusted proportion: 7.7%) vs open group: 9/137 (6.6%); OR 1.19, 95% CI 0.47 to 3.02; 246 participants; four studies; I(2) = 61%) were imprecise. Differences in recurrence at maximal follow-up (laparoscopic group: 37/81 (adjusted proportion based on meta-analysis estimate: 36.3%) vs open group: 59/103 (49.5%); OR 0.58, 95% CI 0.32 to 1.05; 184 participants; two studies; I(2) = 13%), adverse events of any severity (laparoscopic group: 33/109 (adjusted proportion: 31.7%) vs open group: 45/137 (32.8%); OR 0.95, 95% CI 0.54 to 1.66; 246 participants; four studies; I(2) = 18%) and proportion of participants with positive resection margins (laparoscopic group: 49/333 (adjusted proportion based on meta-analysis estimate: 14.3%) vs open group: 208/1133 (18.4%); OR 0.74, 95% CI 0.49 to 1.10; 1466 participants; 10 studies; I(2) = 6%) were also imprecise. Mean length of hospital stay was shorter by 2.43 days in the laparoscopic group than in the open group (MD -2.43 days, 95% CI -3.13 to -1.73; 1068 participants; five studies; I(2) = 0%). None of the included studies reported quality of life at any point in time, recurrence within six months, time to return to normal activity and time to return to work or blood transfusion requirements.
  
  
  CONCLUSIONS
  Currently, no randomised controlled trials have compared laparoscopic distal pancreatectomy versus open distal pancreatectomy for patients with pancreatic cancers. In observational studies, laparoscopic distal pancreatectomy has been associated with shorter hospital stay as compared with open distal pancreatectomy. Currently, no information is available to determine a causal association in the differences between laparoscopic versus open distal pancreatectomy. Observed differences may be a result of confounding due to laparoscopic operation on less extensive cancer and open surgery on more extensive cancer. In addition, differences in length of hospital stay are relevant only if laparoscopic and open surgery procedures are equivalent oncologically. This information is not available currently. Thus, randomised controlled trials are needed to compare laparoscopic distal pancreatectomy versus open distal pancreatectomy with at least two to three years of follow-up. Such studies should include patient-oriented outcomes such as short-term mortality and long-term mortality (at least two to three years); health-related quality of life; complications and the sequelae of complications; resection margins; measures of earlier postoperative recovery such as length of hospital stay, time to return to normal activity and time to return to work (in those who are employed); and recurrence of cancer.
authors.affiliation: Department of Surgery, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands.
authors.forename: Deniece
authors.initials: D
authors.lastname: Riviere
authors.forename: Kurinchi Selvan
authors.initials: KS
authors.lastname: Gurusamy
authors.forename: David A
authors.initials: DA
authors.lastname: Kooby
authors.forename: Charles M
authors.initials: CM
authors.lastname: Vollmer
authors.forename: Marc G H
authors.initials: MG
authors.lastname: Besselink
authors.forename: Brian R
authors.initials: BR
authors.lastname: Davidson
authors.forename: Cornelis J H M
authors.initials: CJ
authors.lastname: van Laarhoven
mesh_terms: D016022:Case-Control Studies; D006801:Humans; D010535:Laparoscopy / Q000009:adverse effects / Q000401:mortality; D010180:Pancreatectomy / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D010190:Pancreatic Neoplasms / Q000601:surgery*; D012189:Retrospective Studies