Inferior mesenteric vein serves as an alternative guide for transection of the pancreatic body during pancreaticoduodenectomy with concomitant vascular resection: a comparative study evaluating perioperative outcomes

Background: Tumors of the pancreatic head often involve the superior mesenteric and portal veins. The purpose of this study was to assess perioperative outcomes after pancreaticoduodenectomy (PD) with concomitant vascular resection using the inferior mesenteric vein (IMV) as a guide for transection of the pancreatic body (Whipple at IMV, WATIMV). Methods: One hundred thirty-seven patients had segmental vein resection during PD between January 2006 and June 2013. Depending on whether the standard approach of creating a tunnel anterior to the mesenterico-portal vein (MPV) axis was achieved for pancreatic transection, patients were subjected to a standard PD with vein resection procedure (s-PD + VR, n = 75) or a modified procedure (m-PD + VR, n = 62). Within the m-PD + VR group, 28 patients underwent the WATIMV procedure, while 34 patients underwent the usual procedure of transection, or 'central pancreatectomy' (c-PD + VR). Results: The volume of intraoperative blood loss and the blood transfusion requirements were significantly greater, and the venous wall invasion and neural invasion frequency were significantly higher in the m-PD + VR group compared with the s-PD + VR group. There were no significant differences in the length of hospitalization, postoperative morbidity, and grades of complications between the two groups. Multivariate logistic regression identified intraoperative blood transfusion (P = 0.004) and vascular invasion (P = 0.008) as the predictors of postoperative morbidity. Further stratification of the entire cohort of 62 (45%) patients who underwent m-PD + VR showed a higher rate of negative resection margins (96.4%) in the WATIMV group compared with the c-PD + VR group (76.5%) (P = 0.06). The volume of intraoperative blood loss (P = 0.013), and intraoperative blood transfusion requirements (P = 0.07) were significantly greater in the c-PD + VR group compared with the WATIMV group. Furthermore, high intraoperative blood loss and tumor stage were predictive of a positive resection margin. Conclusions: 'Whipple at the IMV (WATIMV)' has comparable postoperative morbidity with standard PD + VR. If IMV runs into the splenic vein, it could serve as an alternative guide for transection of the pancreatic body during PD + VR.