Long-term outcomes following en bloc resection for pancreatic ductal adenocarcinoma of the head with portomesenteric venous invasion

BackgroundThe aim of this study is to clarify the prognostic influence of venous resection of the portal vein (PV) or superior mesenteric vein (SMV) on long-term outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) of the head with suspected vascular invasion.MethodsFrom May 1995 to December 2014, a total of 557 patients underwent surgery with curative intent for pancreatic cancer of the head.ResultsAmong 557 patients, 106 (19%) underwent pancreaticoduodenectomy (PD) with PV-SMV resection and 89 (75.5%) of these patients were confirmed to have true pathological invasion. The 5-year overall survival rate in patients underwent PV-SMV resection was significantly lower compared with those who did not (18.7% versus 24.3%; p = 0.002). Patients with negative resection margins who underwent PV-SMV resection had a better prognosis than those with positive resection margins who did not undergo PV-SMV resection with positive resection margins (17% versus 6.3% in 5-year overall survival rate; p = 0.003). The overall morbidity rate was not significantly different between PV-SMV resection group and no PV-SMV resection group (p = 0.064). On multivariate analysis, margin status, advanced T stage (3 or 4), lymph node metastasis, and adjuvant therapy were independent prognostic factors for survival.ConclusionPV-SMV resection was related to lower overall survival. However, on multivariate analysis, margin status was a more important prognostic factor than PV-SMV resection and true pathological invasion for survival. Therefore, en bloc PV-SMV resection should be performed when PV-SMV invasion is suspected to achieve R0 resection.