Abstract
BACKGROUND: Whether the portal/superior mesenteric vein (PV) should be resected during pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) based on preoperative CT or intraoperative findings is controversial. METHODS: This was a retrospective study with data of patients who had undergone pancreatoduodenectomy for PDAC between 2002 and 2016 in a tertiary referral centre. Based on the extent of contact between the PV and tumour on CT, patients were categorized into: group 1, no contact; group 2, contact 180° or less; group 3, contact greater than 180°. Extent of pathological PV invasion (pPV) (no invasion, pv0; invasion to tunica adventitia, pv1; invasion to media, pv2; invasion to intima, pv3) was compared with patient survival. To assess the feasibility of performing PV resection (PVR) based on intraoperative findings, the prognosis of patients in groups 1 and 2 with pv0 and no PVR (PVR(-)pv0) was compared with that of patients who had PVR (PVR(+)pv0), selected using propensity score matching. RESULTS: Groups 1, 2 and 3 comprised 230, 232 and 38 patients respectively, and PVR was performed in 10·9, 73·3 and 95 per cent of them (P < 0·001). Extent of pPV differed significantly (P < 0·001). The positive predictive value of radiological tumour contact with PV in predicting positive pPV was 42·6 per cent. In 64 patients with PVR(-)pv0 and 64 matched patients with PVR(+)pv0, the R0 resection rate (66 versus 73 per cent respectively; P = 0·337) and survival (median 32·4 versus 32·1 months; P = 0·780) were not significantly different. CONCLUSION: PVR is needed only when the tumour is in clear contact with the PV and cannot be detached during surgery.