Research articlePancreatic adenocarcinoma: A simple CT score for predicting margin-positive resection in patients with resectable disease

- Size and location of resectable pancreatic adenocarcinomas are the main factors associated with resection status.
- Presence of a contact between tumor and superior mesenteric/portal vein confluence was not associated with an R1 resection in multivariate analysis.
- A simple CT score based on tumor size and location can help predicting an R1 resection.
- Tumors involving the uncinate process or the neck and with maximal diameter ≥ 20 mm are at high-risk of an R1 resection.
- Tumors located elsewhere (except the pancreaticoduodenal interface) and with a maximal diameter ≥ 30 mm are at high-risk of an R1 resection.

BackgroundNegative-margin status is a prognostic indicator for long-term survival following curative intent resection for pancreatic adenocarcinoma. Patients at increased risk for positive-margin resections may benefit from neoadjuvant chemotherapy prior to resection.MethodsWe retrospectively analyzed preoperative computed-tomography (CT) scans in 108 consecutive patients that underwent curative intent resection for a resectable pancreatic ductal adenocarcinoma from 2009 to 2016 in two academic hospitals. Two radiologists independently staged the tumor, including tumor location, size, and tumor-to-superior mesenteric/portal vein (SMV/PV) contact. Uni and multivariate analysis were performed to identify independent predictors of an R1 resection.ResultsTwenty-nine patients had an R1 resection (26.9%). Tumor size, location, and presence of tumor-to-SMV/PV contact were significantly associated with an R1 resection. In multivariate analysis, the independent parameters associated with resection status were: tumor size (R2 = 9.7), and tumor location (neck R2 = 6.6; pancreaticoduodenal interface R2 = 4.4; uncinate process R2 = 4.1), but not tumor-to-SMV/PV contact (R2 = 0.1, p = 0.7). A simple CT score was built based on tumor size and location. Patients with an R0 resectability score ≥3, i.e. patients with tumor size ≥30 mm (except when tumor location is at the pancreatico-duodenal interface) or patients with tumor size ≥20 mm AND tumor located in the uncinate process or neck, were at high-risk of an R1 resection (AUC, 0.82; sensitivity, 79%; specificity, 76%). This score also showed good diagnostic performances for predicting an R1 resection involving the medial resection margin only (AUC, 0.85).ConclusionsA simple score based on tumor location and size can accurately predict patients at high-risk of an R1 resection.