Long-term outcomes after pancreaticoduodenectomy using pair-watch suturing technique: Different roles of pancreatic duct dilatation and remnant pancreatic volume for the development of pancreatic endocrine and exocrine dysfunction

Background We evaluated long-term outcomes including endo- and exocrine functions after pancreaticoduodenectomy (PD) with standardized pancreaticojejunostomy, paying attention to postoperative pancreatic duct dilatation (PDD) and remnant pancreatic volume (RPV), and examined whether postoperative pancreatic fistula (POPF) influenced the configuration of remnant pancreas. Methods We analyzed the records of 187 patients with PD who could have RPV measured by CT volumetry at 1 month after operation and had been followed for more than 6 months. We assessed the risk factors of diabetes mellitus (DM) and PDD, and evaluated association between RPV and pancreatic endo- and exocrine functions assessed by several markers such as albumin, cholesterol, amylase and HbA1c. Results Regarding RPV, pancreatic exocrine functions were significantly impaired in the small-volume group (SVG: less than 10 ml) than in the large-volume group (LVG: 10 ml or more). The incidence of new-onset or exacerbation of DM did not differ between SVG and LVG. PDD and the primary disease (pancreatic ductal adenocarcinoma compared to bile duct cancer) were selected as the independent risk factors of new-onset or exacerbation of DM by multivariate analysis. Unexpectedly, there was no significant association between POPF and PDD. Conclusions Early occurrence of POPF after PD did not influence the development of PDD in late period, and long-term follow-up should be made by paying attention to PDD and RPV, because PDD was recognized as the most important risk factor of new-onset or exacerbation of DM and the patients with small RPV suffered from prolonged exocrine dysfunction rather than endocrine dysfunction.