Purpose: This systematic review evaluated the diagnostic accuracy and impact on patient management of hepatocyte-specific gadoxetic acid enhanced magnetic resonance imaging (GA-MRI) compared to contrast enhanced computed tomography (CE-CT) in patients with liver metastases.
Method: Four biomedical databases (PubMed, EMBASE, Cochrane Library, York CRD) were searched from January 1991 to February 2016. Studies investigating the accuracy or management impact of GA-MRI compared to CE-CT in patients with known or suspected liver metastases were included. Bias was evaluated using QUADAS-II. Univariate meta-analysis of sensitivity ratios (RR) were conducted in the absence of heterogeneity, calculated using I 2 , Tau values (τ) and prediction intervals.
Results: Nine diagnostic accuracy studies (537 patients with 1216 lesions) and four change in management studies (488 patients with 281 lesions) were included. Per-lesion sensitivity and specificity estimates for GA-MRI ranged from 86.9-100.0 % and 80.2-98.0 %, respectively, compared to 51.8-84.6 % and 77.2-98.0 % for CE-CT. Meta-analysis found GA-MRI to be significantly more sensitive than CE-CT (RR = 1.29, 95 % CI = 1.18-1.40, P < 0.001), with equivalent specificity (RR = 0.97, 95 % CI 0.910-1.042, P = 0.44). The largest difference was observed for lesions smaller than 10 mm for which GA-MRI was significantly more sensitive (RR = 2.21, 95 % CI = 1.47-3.32, P < 0.001) but less specific (RR = 0.92, 95 % CI 0.87-0.98, P = 0.008). GA-MRI affected clinical management in 26 of 155 patients (16.8 %) who had a prior CE-CT; however, no studies investigated the consequences of using GA-MRI instead of CE-CT.
Conclusion: GA-MRI is significantly more sensitive than CE-CT for detecting liver metastases, which leads to a modest impact on patient management in the context of an equivocal CE-CT result.
Keywords: Contrast-enhanced MRI; Diagnostic accuracy; Gadoxetic acid; Gd-EOB-DPTA; Liver metastases.