Introduction : To assess the ability of CT-determined resectability, as defined by National Comprehensive Cancer Network (NCCN) criteria, and associated CT findings to predict margin-negative (R0) resection in patients with pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant FOLFIRINOX chemotherapy

Methods : Sixty-four patients (36 men and 28 women; mean age, 58.8 years) with borderline resectable or unresectable PDAC who received neoadjuvant FOLFIRINOX were evaluated. CT findings were independently assessed by two abdominal radiologists according to NCCN criteria (version 2. 2017). Tumor resectability was classified as resectable, borderline resectable, or unresectable, and change in resectability was classified as regression, stable, or progression. The associations of R0 resection rate with CT-determined resectability and change in resectability categories were evaluated, as were the sensitivity and specificity of NCCN criteria for R0 resection. Factors associated with R0 resection were identified by logistic regression analysis.

Results : R0 resection rate did not differ significantly among the three resectability (67–73%, p=0.95) or the three changes in resectability categories (60–77%, p=0.46). The sensitivity and specificity for R0 resection were 67% and 37%, respectively, for resectability (resectable/borderline vs. unresectable) and 80% and 21%, respectively, for changes in resectability (regression/stable vs. progression). Low contrast enhancement of soft-tissue contacting artery (≤46.4 HU) was independently associated with R0 resection (p=0.01).

Conclusions : CT-determined resectability after neoadjuvant chemotherapy was less sensitive and non-specific for predicting R0 resection. Low contrast enhancement of soft-tissue contacting artery may increase the ability of CT to predict complete resection.