Vascular reconstruction of locally advanced pancreatic cancer: Tricks of the trade

Abstract

Presenter: A. Floortje van Oosten MD | Johns Hopkins University School of Medicine Background: Improved systemic and radiation therapies administered as induction therapy have driven a trend of more aggressive operations in patients with locally advanced pancreatic ductal adenocarcinoma (PDAC) that was historically considered technically unresectable. Previously, we have reported the efficacy and safety of this practice. Herein, we present a technical report describing our surgical experience of tumors considered locally advanced with long segment encasement of the superior mesenteric vein (SMV), celiac axis (CA), or the inferior pancreaticoduodenal artery (IPDA) or gastroduodenal artery (GDA) preluding distal pancreatectomy-celiac axis resection (DP-CAR). We present novel surgical approaches, including reconstruction techniques using mesocaval shunts, non-anatomic bypasses and separate reconstruction of multiple SMV tributaries. Additionally, we assessed the ability to predict resectability using high-quality imaging, in patients with superior mesenteric artery (SMA) involvement. Methods: Our single institutional surgical experience was used to describe the technical aspects of patient selection and surgical techniques to manage the aforementioned tumors. Results: The surgical approaches were stratified by tumor location and type of vessel involvement. Reconstructions were performed using banked cryopreserved vein, left renal vein, tubularized falciform ligament, or tubularized bovine pericardium. SMV Involvement or Occlusion with Multiple Collaterals With complete occlusion of the SMV and involvement of the insertion of the tributaries and well-developed left sided collaterals, the SMV does not need to be reconstructed if the collaterals can be preserved. However, dominant collateral circulation is absent a temporary mesocaval shunt can be performed prior to resection. The option then remains to keep the mesocaval shunt and implant the other branch into the portal vein or to transpose the mesocaval shunt to the portal vein. An extra-anatomic bypass is performed from the ileal and/or jejunal branch to the portal vein in patients with involvement of the ileal and jejunal tributaries, and occlusion of the SMV up to the confluence of the splenic and portal vein. If SMV involvement reaches the level of the main tributaries, multiple non-anatomic reconstructions of the ileal and jejunal tributaries can be performed (Figure1). GDA, IPDA, and CA Encasement In patients with GDA and/or IPDA involvement a DP-CAR is not possible. If an acceptable distal target is present a bypass graft can be placed between the aorta, celiac cuff, right renal artery, or iliac artery to the CHA or the proper hepatic artery (PHA). DP-CAR can be performed if a replaced left hepatic artery is present, which can be reimplanted into the CHA, through which it receives retrograde flow. SMA Encasement Two types of SMA encasement were identified on imaging: true encasement/invasion and encasement with a “halo” sign. Narrowing of the SMA lumen is indicative of true invasion making SMA preservation not possible. In cases of a “halo” sign in our experience a margin negative resection is possible without SMA resection. Conclusion: Here we describe surgical approaches to successful resection of variants of locally advanced PDAC as stratified by the vessels involved. With increasing utilization of these techniques a need to revise the current definitions of tumor staging seems imminent.