Utility of contrast-enhanced harmonic EUS in the diagnosis of malignant gallbladder polyps (with videos)

Abstract

Background: The differential diagnosis between benign and malignant polyps of the gallbladder (GB) is often challenging.

Objectives: To evaluate whether contrast-enhanced harmonic EUS (CEH-EUS) might be an accurate method for discriminating malignant GB polyps from benign polyps.

Design: Observational study.

Setting: Tertiary care medical center.

Patients: Ninety-three patients with GB polyps larger than 10 mm in diameter that were detected by conventional EUS underwent CEH-EUS for evaluation of microvasculature.

Intervention: CEH-EUS was performed using a radial echoendoscope and the extended pure harmonic detection mode.

Main outcome measurements: The abilities of conventional EUS and CEH-EUS to diagnose malignant polyp were compared. Two blinded reviewers classified the perfusion images into 3 categories: diffuse enhancement, perfusion defect, or nonenhancement. The vessel images were categorized as having a regular spotty vessel, an irregular vessel, or no vessels.

Results: An irregular vessel pattern determined by CEH-EUS aided in the diagnosis of malignant polyps with a sensitivity and specificity of 90.3% and 96.6%, respectively. The presence of perfusion defects, determined by CEH-EUS, was calculated to diagnose malignant polyps with a sensitivity and specificity of 90.3% and 94.9%, respectively. Based on the definitely determined diagnosis, sensitivity and specificity for CEH-EUS were 93.5% and 93.2% versus 90.0% and 91.1% for conventional EUS. In 8 cases, management changed after CEH-EUS.

Limitations: A tertiary medical center with a limited number of patients.

Conclusions: The presence of irregular intratumoral vessels or perfusion defects seen on CEH-EUS may be sensitive and accurate predictors of malignant GB polyps. CEH-EUS offers slightly improved diagnostic accuracy compared with EUS.

Keywords: CEH; CI; GB; SD; confidence interval; contrast-enhanced harmonic; gallbladder; standard deviation.