Two-dimensional Shear Wave Elastography: Utility in Differentiating Gallbladder Cancer From Chronic Cholecystitis.

Abstract

To study the utility of 2D shear wave elastography (SWE) and ascertain cut-off values of shear wave elasticity (SWe) to differentiate benign and malignant thickening of the gallbladder wall. This study was a prospective study of patients with symptomatic gallstone disease (GSD, n=51) and gallbladder cancer (GBC, n=46) and controls without any biliary disease (n=46). All the participants underwent 2D USG and SWE of the gallbladder. Grey-scale ultrasound and SWE were done in the different regions in the gallbladder. The median age of the patients with GSD was 49 years (interquartile range [IQR]: 33-55), GBC was 55 years (IQR: 46-65), and controls was 37 years (IQR: 27-48.25). In patients with GBC, asymmetrical mural thickening was the predominant imaging pattern (n=24, 52.2%). The mean SWe of the abnormal area in GBC (34.99 ± 17.77 kPa [n=46]) was significantly higher than that of the uninvolved region (18.27 ± 8.12 kPa [n=35]; P < .01). The mean SWe of the uninvolved region in GBC (18.27 ± 8.12 kPa [n=35]) was also significantly higher (P < .01) than that of GSD (12.27 ± 4.13 kPa [n=51]) and controls (10.52 ± 3.75 kPa [n=46]). On ROC analysis, AUC of 0.927, at a cut-off of 20 kPa, sensitivity was 91.3%, specificity was 83.5%, positive likelihood ratio was 5.54, and negative likelihood ratio was 0.10 to diagnose GBC. The 2D SWE is a reliable adjunctive tool to grey-scale USG in differentiating the malignant from benign gallbladder wall and may help to pick up early malignancy in GSD.