Pancreatic atrophy relative to external versus internal drainage of the pancreatic duct after pylorus-preserving pancreaticoduodenectomy.

Background: Atrophy of the pancreatic parenchyma, which occurs frequently after pylorus-preserving pancreaticoduodenectomy (PPPD), is often associated with pancreatic exocrine insufficiency. Many surgeons prefer to insert a drainage tube into the remnant pancreatic duct primarily to prevent pancreatic leakage at the pancreaticojejunostomy (PJ) after PPPD. Drainage methods vary widely but can be roughly classified as internal or external drainage. This study intended to evaluate their effects on pancreatic parenchymal atrophy following PPPD.

Methods: Fifty-seven patients who underwent PPPD were retrospectively divided into two groups, 28 who underwent external and 29 who underwent internal pancreatic drainage. External drainage tubes were removed 4 weeks after PPPD. The volume of the pancreatic parenchyma was serially measured on abdominal computed tomography (CT) scans before PPPD, as well as 7 days and 3, 6, and 12 months after surgery. Degree of pancreatic parenchymal atrophy was determined by calculating pancreatic volume relative to that on day 7.

Results: Univariate analysis showed that patient sex, age, body mass index, concurrent pancreatitis, pathology, and types of PJ did not significantly affect changes in pancreatic volume following PPPD. The degree of pancreatic volume atrophy did not differ significantly in the external and internal drainage groups. No patient in the external drainage group experienced drainage-related surgical complications. The incidence of PJ leak was comparable in the two groups. Postoperative pancreatic atrophy did not induce new-onset diabetes mellitus at 1 year.

Conclusions: Both external and internal pancreatic drainage methods showed similar atrophy rate of the pancreatic parenchyma following PPPD.