The primary study endpoints were; pancreatic fistula rates, severity of pancreatic fistulas, postoperative complications, postoperative length of hospital stay, and hospital mortality rate. Pancreatic fistula was defined as any measurable drainage from an operatively placed drain (or a subsequently placed percutaneous drain) on or after postoperative day 3, with an amylase content greater than 3 times the upper limit of normal serum amylase level (i.e., >300 IU/L)(International Study Group for Pancreatic Fistulas (ISGPF) definition) or on or after postoperative week 1 drainage of more than 30 mL of fluid with an amylase level higher than 600 U/dL(Seoul National University Hospital (SNUH) definition). In addition, fistula severity was graded as A, B, C according to ISGPF clinical criteria as follows; grade A fistula - a transient, asymptomatic fistula with only elevated drain amylase levels and treatments or deviation in clinical management are not required; grade B fistula - a symptomatic, clinically apparent fistula requiring diagnostic evaluation and therapeutic management; and grade C fistula - a severe, clinically significant fistula requiring a major deviations in clinical management and unequivocal aggressive therapeutic interventions. Major pancreatic leakage was defined as drainage of more than 200 mL of fluid or the development of an intra-abdominal abscess.