Utility of Contrast-Enhanced Ultrasound in Differentiation between Benign Mural Lesions and Adenocarcinoma of Gallbladder.

Background: Mural lesions of gallbladder on ultrasound (US) are often difficult to characterize as benign or malignant.

Purpose: The aim of the study was to evaluate the role of contrast-enhanced US (CEUS) in characterization of gallbladder (GB) wall lesions and making distinction between benign wall thickening and GB adenocarcinoma, utilizing both quantitative and qualitative parameters.

Methods: A total of 26 patients with GB wall lesions detected on sonography underwent CEUS. Lesions were evaluated on the basis of morphological imaging features, enhancement pattern, dynamic real-time contrast uptake, and intralesional vascularity.

Results: Overall, 19 patients had final diagnosis of GB adenocarcinoma, whereas seven patients had benign etiology. CEUS has enabled the differentiation of nonenhancing tumefactive sludge from enhancing mural lesions, thus improving the accuracy of morphological assessment of lesions. The intactness of outer wall was better assessed on CEUS. The dynamic postcontrast assessment showed that carcinoma showed early washout of contrast compared to benign thickening ( = 0.002). Nonlayered mural enhancement or thick enhancing inner layer with nonenhancing thin outer layer was associated with adenocarcinoma. The classification of intralesional vascularity on CEUS was not helpful in distinguishing benign lesions and adenocarcinoma.

Conclusion: CEUS can increase the diagnostic confidence in differentiation between benign mural lesions and adenocarcinoma of GB.