Impact of post-operative superior mesenteric/portal vein stenosis on survival outcomes among pancreatic head ductal adenocarcinoma patients undergoing pancreaticoduodenectomy with combined venous resection following neoadjuvant chemoradiotherapy: A single-center retrospective study.

BACKGROUND: The study aimed at assessing the impact of post-operative superior mesenteric/portal vein (SMV/PV) stenosis on survival outcomes in pancreatic head ductal adenocarcinoma patients undergoing pancreaticoduodenectomy (PD) with combined venous resection following neoadjuvant chemoradiotherapy. METHODS: From April, 2007 to August, 2022, 226 patients were enrolled and among them, 185 underwent PD with SMV/PV resection. In these, 53.5% (99/185) developed stenosis were, 23 (23.2%) had early (≤30 days) while 76 (76.8%) had late (>30 days) stenosis' onset. Prognostic predictors of stenosis and survival outcomes were also identified. RESULTS: Patients with stenosis had a greater tumor-SMV/PV interface, more advanced tumors, intra-operative blood loss, longer operation times and inferior survival outcomes compared to those without. Median survival times (MST) for overall survival (OS) were 28.7 (no stenosis) vs. 23.1(with stenosis), months (p=0.034). Similarly based on onset, OS were 12.9 (early) vs. 26.7 (late), months (p=0.005). Predictors of stenosis included T-category, tumor-SMV/PV interface, SMV/PV resection length and CD ≥ III complications. In the entire cohort, stenosis was an independent adverse prognostic factor of OS (HR 2.29, p<0.001). Among patients with stenosis, early onset of stenosis was further prognostic for poor OS (HR 2.285, p=0.003). CONCLUSION: Post-operative SMV/PV stenosis was an independent predictor of poor survival after PD, especially when onset was early. Its predictors included advanced tumor status, tumor-SMV/PV interface, SMV/PV resection length and CD ≥ III complications, emphasizing the need for careful surgery and close follow-up.