Abstract: In two eligible trials, a total of 381 participants underwent distal pancreatic resection and were randomised to closure of the pancreatic remnant either with stapler (n = 191) or scalpel resection followed by hand-sewn closure (n = 190). One was a single centre pilot RCT and the other was a multicentre blinded RCT. The single centre pilot RCT evaluated 69 participants in five intervention arms (stapler, hand-sewn, fibrin glue, mesh and pancreaticojejunostomy), although we only assessed the stapler and hand-sewn closure groups (14 and 15 participants, respectively). The multicentre RCT had two interventional arms: stapler (n = 177) and hand-sewn closure (n = 175). The rate of postoperative pancreatic fistula was the main outcome, and it occurred in 79 of 190 participants in the hand-sewn group compared to 65 of 191 participants in the stapler group. Neither the individual trials nor the meta-analysis showed a significant difference between resection techniques (RR 0.90; 95% CI 0.55 to 1.45; P = 0.66). In the same way, postoperative mortality and operation time did not differ significantly. The single centre RCT had an unclear risk of bias in the randomisation, allocation and both blinding domains. However, the much larger multicentre RCT had a low risk of bias in all domains. Due to the small number of events and the wide confidence intervals that cannot exclude clinically important benefit or harm with stapler versus hand-sewn closure, there is a serious possibility of imprecision, making the overall quality of evidence moderate. The quality of evidence is moderate and mainly based on the high weight of the results of one multicentre RCT. Unfortunately, there are no other completed RCTs on this topic except for one relevant ongoing trial. Neither stapler nor scalpel resection followed by hand-sewn closure of the pancreatic remnant for distal pancreatectomy showed any benefit compared to the other method in terms of postoperative pancreatic fistula, overall postoperative mortality or operation time. Currently, the choice of closure is left up to the preference of the individual surgeon and the anatomical characteristics of the patient. Another (non-European) multicentre trial (e.g. with an equality or non-inferiority design) would help to corroborate the findings of this meta-analysis. Future trials assessing novel methods of stump closure should compare them either with stapler or hand-sewn closure as a control group to ensure comparability of results.

Plain-language summary: We searched several electronic databases to find high quality trials about this topic. Two authors independently read reports on the trials to decide whether or not to include them in the review, and they independently extracted the trial data so as not to miss any important information. The search yielded two high quality trials including a total of 381 participants. The statistical analyses resulted in similar rates of pancreatic fistula (about 35%), deaths after surgery (about 1%) and average operation time between the two operation methods. Individual surgeons can choose which closure technique to use after removing of the tail of the pancreas according to their preferences and the participant's anatomic characteristics. More high quality trials on this topic would be beneficial, and studies investigating new methods should compare them either to stapler or hand-sewn closure in order to ensure comparability of results.