High Incidence of Anastomotic Stenosis in Pancreatoduodenectomy with Distal Portal Vein Resection: An Ileocolic Vein-Based Anatomical Definition.

Abstract

Anastomotic stenosis after portal vein resection during pancreaticoduodenectomy for pancreatic cancer can result in portal hypertension-related complications, although the anatomical determinants of stenosis remain poorly defined. We evaluated whether the level of superior mesenteric vein (SMV) transection influences postoperative portal vein stenosis after segmental portal vein resection. Patients who underwent pancreaticoduodenectomy with segmental portal vein resection for borderline resectable or locally advanced pancreatic cancer at two centers were retrospectively analyzed. Proximal transection was defined as SMV transection proximal to the ileocolic vein confluence, whereas distal transection was defined as transection at or distal to the ileocolic vein confluence. The primary outcome was non-tumorous anastomotic stenosis. Among 276 patients, 232 underwent proximal transection and 44 underwent distal transection. Non-tumorous anastomotic stenosis occurred more frequently after distal than proximal transection (40.9% vs 1.7%, p < 0.01). Symptomatic stenosis associated with refractory ascites, varices, or gastrointestinal bleeding was also more common in the distal group (15.9% vs 1.2%, p < 0.01). On multivariable analysis, distal SMV transection independently predicted anastomotic stenosis, whereas portal vein resection length was not associated with stenosis risk. SMV transection at or distal to the ileocolic vein confluence was strongly associated with postoperative anastomotic stenosis and clinically significant portal hypertension-related complications after pancreaticoduodenectomy with portal vein resection. These findings suggest that peripheral SMV reconstruction represents a distinct technical risk factor independent of resection length.