Remnant pancreatic volume is associated with externalized pancreatic duct stent output and clinically relevant pancreatic fistula after pancreaticoduodenectomy

Postoperative pancreatic exocrine secretion is considered a key factor in the development of the clinically relevant postoperative pancreatic fistula (CR-POPF), but it can only be measured in patients with externalized pancreatic duct stents. This study aimed to determine whether preoperative remnant pancreatic volume (RPV) can serve as a marker of postoperative externalized pancreatic duct stent output and predict CR-POPF. We retrospectively analyzed 95 patients who underwent pancreaticoduodenectomy (PD) (2021–2022). RPV was measured using contrast-enhanced CT with SYNAPSE VINCENT. The maximum daily externalized pancreatic duct stent output was recorded as a surrogate measure of remnant pancreatic exocrine secretion. Correlation and comparative analyses evaluated the predictive value of RPV for externalized pancreatic duct stent output and CR-POPF. Externalized pancreatic duct stent output showed the highest predictive performance for CR-POPF. Although direct measurement is limited to patients with externalized pancreatic duct stents, RPV strongly correlated with externalized pancreatic duct stent output ( R = 0.743) and demonstrated comparable predictive performance for CR-POPF. An RPV cutoff of 28.5 mL effectively identified high-risk patients. RPV may serve as a practical surrogate marker of postoperative externalized pancreatic duct stent output, providing a potential physiological explanation for its association with CR-POPF.