Real time endoscopic ultrasound elastography and strain ratio in the diagnosis of solid pancreatic lesions

Abstract

AIMTo evaluate the accuracy of the elastography score combined to the strain ratio in the diagnosis of solid pancreatic lesions (SPL).METHODSA total of 172 patients with SPL identified by endoscopic ultrasound were enrolled in the study to evaluate the efficacy of elastography and strain ratio in differentiating malignant from benign lesions. The semi quantitative score of elastography was represented by the strain ratio method. Two areas were selected, area (A) representing the region of interest and area (B) representing the normal area. Area (B) was then divided by area (A). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated by comparing diagnoses made by elastography, strain ratio and final diagnoses.RESULTSSPL were shown to be benign in 49 patients and malignant in 123 patients. Elastography alone had a sensitivity of 99%, a specificity of 63%, and an accuracy of 88%, a PPV of 87% and an NPV of 96%. The best cut-off level of strain ratio to obtain the maximal area under the curve was 7.8 with a sensitivity of 92%, specificity of 77%, PPV of 91%, NPV of 80% and an accuracy of 88%. Another estimated cut off strain ratio level of 3.8 had a higher sensitivity of 99% and NPV of 96%, but with less specificity, PPV and accuracy 53%, 84% and 86%, respectively. Adding both elastography to strain ratio resulted in a sensitivity of 98%, specificity of 77%, PPV of 91%, NPV of 95% and accuracy of 92% for the diagnosis of SPL.CONCLUSIONCombining elastography to strain ratio increases the accuracy of the differentiation of benign from malignant SPL.

Diagnostic Efficacy of Endoscopic Ultrasound Elastography in Differentiating Solid Pancreatic Lesions: A Single-Center Experience

“…We found a cut-off point of 4.55, which had specificity, sensitivity, PPV, NPV, and accuracy of 94.7%, 96.9%, 98.9%, 85.7%, and 96.5%, respectively. This was similar to the results of the study by Okasha and colleagues [11], who reported a cut-off point of 3.8, which had NPV, sensitivity, and accuracy of 86%, 99%, and 96%, respectively, but lower specificity and PPV of 53% and 84%, respectively. Kongkam et al [12] also reported a cut-off point of 3.17, which had lower specificity, sensitivity, PPV, NPV, and accuracy of 66.7%, 86.2%, 89.3%, 60%, and 81.6%, respectively.…”

Diagnostic value of endoscopic ultrasound elastography for benign and malignant digestive system tumors

“…At present, the five-point scoring system is the main method in the diagnosis of benign and malignant lesions; a higher score is corresponding to a higher elasticity coefficient of a lesion compared to normal tissues 15. In this study, the lesions with no less than 3 points were evaluated as malignant lesions and those with no more than 2 points were evaluated as benign lesions.…”

Endoscopic ultrasound (EUS) elastography and strain ratio, could it help in differentiating malignant from benign pancreatic lesions?

“…We previously investigated 172 patients identified to have SPL by the previously mentioned noninvasive modalities beside the EUS-FNA to predict the nature of the lesion. [ 3 ] At the cut-off level of 3.8, we had sensitivity, specificity, PPV, NPV, and accuracy of 99%, 53%, 84%, 86%, and 96%, respectively. Then we calculated the best cut-off value to have 7.8 to differentiate between benign and malignant SPL.…”

“…In a previous study, [ 3 ] we evaluated real-time EUS elastography and strain ratio as predictive tools to reach the correct diagnosis for SPL. It had a sensitivity of 98% and specificity of 77% and a diagnostic accuracy of 92%.…”