Comparison between CT texture data, resection margin status and clinical outcomes in pancreatic adenocarcinoma resected after induction chemotherapy and neoadjuvant stereotactic body radiation therapy

Purpose: The aim of this study is to compare CT texture analysis parameters with the resection margin status, the recurrence-free survival (RFS) and the overall survival (OS) in patients with pancreatic ductal adenocarcinoma (PDAC) resected after induction chemotherapy and neoadjuvant stereotactic body radiotherapy (SBRT). Preoperative prediction of patients who are likely to have positive resection margins and worse clinical outcome is beneficial to avoid early disease recurrence after surgery. Material and Methods: Between January 2017 and May 2019, 134 patients with histologically proven unresectable PDAC underwent induction chemotherapy (FOLFIRINOX or Gemcitabine + Nab-Paclitaxel), followed by radiotherapy. Patients who received surgery after neoadjuvant SBRT were included. 47 texture features were extracted from 3D regions of interest (ROIs) based on unenhanced, arterial- and portal-phase CT images performed for SBRT planning. Clinical features and texture-derived parameters were compared; receiver operating characteristic (ROC) curves were constructed for the features that showed a significant difference between groups. Cox regression analysis and Kaplan–Meier curves were used to determine the association of clinical–pathological variables and texture parameters with RFS and OS. Results: 43 patients (27 males, 16 females; mean age, 65 years; age range, 48–81 years) were included in this retrospective study. 14 patients (32.6%) had vascular resection. Patients with higher arterial HU_Q1 had significantly shorter RFS than patients who did not meet this criterion (p=.032 and .005; mean RFS 9.6 vs 14.8 months and 8 vs 14.3 months, respectively); no significant predictors were found for OS. Conclusion: CT texture analysis could predict RFS in patients