Quantitative evaluation of upper gastrointestinal subepithelial lesions using endoscopic ultrasound-guided shear wave elastography

Shear wave elastography provides quantitative data on tissue stiffness, but was not available for endoscopic ultrasound until recently. The present study investigated the utility of a newly developed endoscopic ultrasound-guided shear wave measurement for diagnosing upper gastrointestinal subepithelial lesions. Shear wave velocity (Vs) was measured as an indicator of tissue stiffness, and the total amount of effective shear waves (VsN) was used as a reliability index for Vs values obtained by endoscopic ultrasound-guided shear wave measurements. Among the Vs values obtained, the five with the highest VsN were selected, and their median was defined as the median Vs (Vs-med). The median VsN of the five Vs values was defined as the median VsN (VsN-med). Endoscopic ultrasound-guided shear wave measurements were performed on 23 patients, with no complications occurring in any procedure. Histopathological diagnoses included 12 gastrointestinal stromal tumors, seven leiomyomas, and four schwannomas. Vs-med values for gastrointestinal stromal tumors, leiomyomas, and schwannomas were 2.46, 1.73, and 2.85 m/s, respectively, indicating that gastrointestinal stromal tumors and schwannomas were significantly stiffer than leiomyomas. VsN-med values for gastrointestinal stromal tumors, leiomyomas, and schwannomas were 40.5, 39, and 35.5%, respectively, with no significant differences. Endoscopic ultrasound-guided shear wave measurements are feasible for upper gastrointestinal subepithelial lesions and allow for the objective, non-invasive quantification of lesion stiffness. These results suggest the potential of endoscopic ultrasound-guided shear wave measurements as a valuable tool for the differential diagnosis of upper gastrointestinal subepithelial lesions.