Clinical outcomes of preservation versus resection of portal/superior mesenteric vein during pancreaticoduodenectomy in pancreatic cancer patients who respond to neoadjuvant treatment: a retrospective cohort study.

Background: R0 rates have increased as neoadjuvant treatment (NAT) has become the primary treatment for pancreatic ductal adenocarcinoma (PDAC) with venous involvement, suggesting a decrease in venous tumor infiltration. The aim of this study was to investigate the clinical outcomes of preserving the portal/superior mesenteric vein (PV/SMV) during pancreaticoduodenectomy (PD) in PDAC patients who underwent NAT.

Methods: The 113 patients with resectable and borderline resectable PDAC with venous involvement who responded to NAT and underwent curative PD between 2012 and 2022 were retrospectively reviewed.

Results: Among the 113 patients, PV/SMV preservation (PVP) was performed in 68 patients (60.2%), and PV/SMV resection (PVR) was performed in 45 patients (39.8%). There was no significant difference in the R0 rate, 5-year overall survival (OS) and recurrence-free survival between the two groups. PV/SMV stenosis within 3 months after surgery was more common in the PVR group than in the PVP group (1.5% versus 22.2%; P <0.001), and 5-year PV/SMV stenosis-free survival was significantly higher in the PVP group than in the PVR group (76.5% versus 53.4%; P =0.014). Multivariate analysis showed that gemcitabine-based neoadjuvant chemotherapy was associated with poor OS. PVR, clinically relevant postoperative pancreatic fistula, and locoregional recurrence were independent risk factors for PV/SMV stenosis.

Conclusions: The PVP group had similar oncologic outcomes and better vessel-functional outcomes than the PVR group. Therefore, if dissection is possible and there is a high likelihood of achieving R0 resection after NAT, routine PVR may be unnecessary in PDAC patients with venous involvement.