Role of Strain Histogram Elastography using Endoscopic Ultrasound for Differentiating Malignant from Benign Pancreatic masses

Abstract

Background: For the differential diagnosis of localized pancreatic masses, endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) are currently the methods of choice. By assessing tissue stiffness, elastography, a minimally invasive approach, improves the accuracy of identifying solid pancreatic lesions using qualitative and quantitative (strain ratio and strain histogram (SH)) methods. This study aimed to assess the reliability of the SH EUS-based technique for the diagnosis of patients with pancreatic masses. Methods: This cross-sectional study was conducted on fifty patients attending Kasr Al-Ainy Hospital. All patients fulfilling the inclusion criteria, were enrolled in the study after ethical approval obtained from the hospital ethical committee of Benha Faculty of Medicine. The patients presented variably with obstructive jaundice, abdominal pain, and cachexia and were investigated with abdominal ultrasound, computed tomography (CT) of the abdomen and pelvis, magnetic resonance imaging (MRI), and full laboratory tests. After fulfilling the criteria of our study, patients underwent EUS with strain histogram elastography and fine needle aspiration with histopathological examination where 35 specimens were found malignant, and 15 specimens were found benign. Results: SH Elastography can significantly predict malignant tumors with an area under the curve (AUC) of 0.914, P value <0.001, and at a cutoff value ≤56 with 94.2% sensitivity, 60.0% specificity, 84.6% positive predictive value (PPV), and 81.8% negative predictive value (NPV). Conclusion:SH showed high sensitivity in pancreatic malignant tumor detection but with moderate specificity.