Pancreatic fistula is one of the most serious complication after pancreatoduodenectomy. To reduce pancreatic fistula, many authors recommend pancreatic stent in pancreatojejunostomy. There are two distinct methods of pancreatic stent insertion: internal stent and external stent. There was few studies comparing these methods in preventing pancreatic fistula. Furthermore, its long-term effect was not known enough. The purpose of this study is to determine which is the best method in preventing pancreatic fistula and to investigate its long term clinical outcomes.

Inclusion Criteria:

• patient who have malignant or benign disease which needs pancreatoduodenectomy
• patient age: ≥20 and ≤85

Exclusion Criteria:

• patient who had chemotherapy or radiotherapy previous to operation.
• patient who had severe comorbid disease(cardiac, pulmonary, cerebrovascular)
• patient who had past medical history of chronic pancreatitis.
• pancreatic stent size <1mm or >5mm