Meta-analysis of contrast-enhanced ultrasound and contrast-enhanced harmonic endoscopic ultrasound for the diagnosis of gallbladder malignancy

Abstract

Background: The diagnosis between benign and malignant gallbladder lesions is sometimes difficult. The objective of this study is to assess whether contrast-enhanced ultrasound (CEUS) and contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) can be an accurate method for detecting gallbladder malignancy and to determine which imaging signs can be indicative of malignancy.

Methods: A study search of PubMed, Elsevier, and Sciencedirect was performed in May 2019. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve were used to examine the accuracy of CEUS and CH-EUS.

Results: Twenty-one studies were included in the meta-analysis. The pooled sensitivities of CEUS and CH-EUS were 0.81 (0.75-0.86) and 0.92 (0.86-0.95); the specificities were 0.94 (0.90-0.96) and 0.89 (0.69-0. 97); the DORs were 64 (32-127) and 89 (22-354); and the area under the SROC curves were 0.90 (0.87-0.92) and 0.92 (0.90-0.94). On CEUS, the diagnostic criterion for gallbladder malignancy according to four features were analyzed. Sensitivity and specificity were 0.75 (0.65-0.83) and 0.98 (0.85-1.00) for integrity of gallbladder wall; 0.69 (0.55-0.81) and 0.89 (0.77-0.95) for heterogeneous enhancement; 0.81 (0.71-0.88) and 0.88 (0.76-0.94) for irregular vessels; and 0.81 (0.66-0.91) and 0.75 (0.59-0.86) for washout time within 28 s. On CH-EUS, heterogeneous enhancement could be indicative of malignant lesions with a sensitivity of 0.94 (0.85-0.97); and the specificity was 0.92 (0.71-0.98).

Conclusions: CEUS and CH-EUS are promising and reliable imaging modalities with a high sensitivity and specificity for the diagnosis of gallbladder malignancy. CH-EUS might be more sensitive than CEUS with a higher sensitivity. In addition, irregular tralesional vessels and washout time within 28 s on CEUS and heterogeneous enhancement on CH-EUS are indicative of malignancy. However, larger scale and well-designed studies are warranted to verify our results.

Keywords: Contrast-enhanced ultrasound; Diagnosis; Endoscopic ultrasonography; Gallbladder; Malignant lesions; Meta-analysis.

Fig. 1

Flowchart of study selection

Fig. 2

Quality assessment of the included studies

Fig. 3

The pooled sensitivity and specificity (a) and summary receiver operating characteristic curve (b) on CEUS for the diagnosis of gallbladder malignancy

Fig. 4

The pooled sensitivity and specificity for the integrity of gallbladder wall on CEUS for the diagnosis of gallbladder malignancy

Fig. 5

The pooled sensitivity and specificity for the enhancement pattern on CEUS for the diagnosis of gallbladder malignancy

Fig. 6

The pooled sensitivity and specificity for the tralesional vascularity on CEUS for the diagnosis of gallbladder malignancy

Fig. 7

The pooled weighted mean differences for the contrast arrival time (a), time to peak enhancement (b), and washout time (c) comparing malignant and benign lesions

Fig. 8

The pooled sensitivity and specificity for the washout time within 28s on CEUS for the diagnosis of gallbladder malignancy

Fig. 9

The pooled sensitivity and specificity (a) and summary receiver operating characteristic curve (b) on CH-EUS for the diagnosis of gallbladder malignancy

Fig. 10

The pooled sensitivity and specificity for the enhancement pattern on CH-EUS for the diagnosis of gallbladder malignancy