Importance: Current recommendations for patients with cirrhosis are to undergo surveillance for hepatocellular carcinoma (HCC) with ultrasonography (US) every 6 months. However, the sensitivity of US screening to detect early-stage HCC is suboptimal. Magnetic resonance imaging (MRI) with liver-specific contrast may detect additional HCCs missed by US in high-risk patients with cirrhosis.
Objective: To compare the HCC detection rate of US and MRI in patients with cirrhosis who are at high risk for HCC.
Design, setting, and participants: A prospective surveillance study of 407 patients with cirrhosis and an estimated annual risk of HCC greater than 5% who underwent 1 to 3 biannual screening examinations with paired US and liver-specific contrast-enhanced MRI at a tertiary care hospital between November 2011 and August 2014. All patients were followed-up with dynamic computed tomography (CT) at 6 months after the study. The confirmation of HCC was based on the results of histologic examination and/or typical CT images of HCC.
Main outcomes and measures: HCC detection rates and false-positive findings of US vs MRI.
Results: A total of 407 eligible patients received 1100 screenings with paired US and MRI. Hepatocellular carcinomas were diagnosed in 43 patients: 1 detected by US only, 26 by MRI only, 11 by both, and 5 were missed by both. The HCC detection rate of MRI was 86.0% (37/43), significantly higher than the 27.9% (12/43) of US (P < .001). Magnetic resonance imaging showed a significantly lower rate of false-positive findings than US (3.0% vs 5.6%; P = .004). Of the 43 patients with HCC, 32 (74.4%) had very early-stage HCC (a single nodule <2 cm), and 29 (67.4%) received curative treatments. The 3-year survival rate of the patients with HCC (86.0%) was not inferior to those without HCC (94.2%; hazard ratio, 2.26; 95% CI, 0.92-5.56; P = .08).
Conclusions and relevance: In patients with cirrhosis at high-risk of HCC, screening that used MRI with liver-specific contrast resulted in a higher HCC detection rate and lower false-positive findings compared with US. With MRI screening, most of the cancers detected were at very early stage, which was associated with a high chance of curative treatments and favorable survival of patients. Whether surveillance with MRI would reduce mortality from HCC in high-risk patients requires further investigation.
Trial registration: clinicaltrials.gov Identifier: NCT01446666.