Pancreatoduodenectomy with venous resection for pancreatic cancer does not improve the R0-rate

Abstract

Introduction: Pancreatoduodenectomy with venous resection is considered standard of care in case of tumor involvement of the portal and/or superior mesenteric vein. It is performed with the aim of achieving an R0-resection. Methods: This prospective observational study included all patients undergoing pancreatoduodenectomy with or without venous resection for pancreatic cancer between January 2015 and October 2017 at Oslo University Hospital. Patients who received neoadjuvant chemotherapy were excluded. Detailed microscopic mapping of the tumour at the superior mesenteric vein (SMV)-groove was undertaken and results were compared between specimens with and without venous resection. Results: Ninety-five patients were included, of whom 25 had pancreatoduodenectomy with venous resection. R0-resection, based on >1 mm clearance, was achieved in 15 of 70 patients (21.4 %) without venous resection and in one of 25 patients (4 %) with venous resection (p=0.061). The SMV margin adjacent to the tethered vein was the most frequently involved margin in both groups (24 of 25, 96 % with venous resection, 35 of 70, 50 % without venous resection; p< 0.001). Microscopic mapping revealed that the broad invasive tumour front at the SMV-groove as well as the absence of peripancreatic adipose tissue at the SMV-margin were responsible for these findings. The transection margins of the venous resection itself were involved in only three of the 25 patients (12 %). Conclusion: R0-resection following pancreatoduodenectomy with venous resection can rarely be achieved due to involvement of the SMV-margin immediately adjacent to the resected vein.