Postoperative Refractory Diarrhea After Margin Accentuation of the Superior Mesenteric Artery with Irreversible Electroporation in Pancreaticoduodenectomy.

Background: Pancreatic ductal adenocarcinoma (PDAC) presents a challenge due to its poor prognosis. Irreversible electroporation (IRE) shows promise in improving margin clearance and increasing R0 and R1 indirect resection rates. Although IRE is believed to preserve surrounding tissues, this study aimed to assess postoperative refractory diarrhea as a severe complication and challenge the assumption of consistent tissue preservation. Methods: Patients undergoing pancreaticoduodenectomy (PD) with IRE for superior mesenteric artery (SMA) margin accentuation between May 2022 and April 2024 were included. Primary endpoints were diarrhea-related morbidity and mortality; secondary endpoints included R-status, recurrence, and metastases. IRE electrodes were initially positioned circumferentially around the SMA, but this approach was modified to hemi-circumferential placement and applied in six additional patients. Results: All five patients (median age 70, 80% female) in the initial cohort developed secretory diarrhea lasting a median of 6 months (IQR 5-6.5), with a median frequency of 5 stools/day (IQR 5-6.5). Two patients (40%) died due to diarrhea-associated cachexia. In contrast, among the six patients treated with the modified technique, patients' diarrhea resolved within a median of 8 days (IQR 6-10) without need for opioid or advanced antidiarrheal therapy. Conclusions: Circumferential IRE for SMA margin accentuation may damage the superior mesenteric plexus and induce severe, prolonged diarrhea. Hemi-circumferential application may mitigate this risk. Larger studies are required to validate these findings and optimize the use of IRE in PD.