Abbreviated MRI Using Gadoxetic Acid Versus Ultrasonography for Surveillance of Early-stage HCC in Patients at High Risk

Hepatocellular carcinoma (HCC) is the third most frequent cause of cancer-related deaths worldwide. The incidence of HCC has been rapidly rising worldwide over the last two decades. In order to improve survival with curative treatment, regular surveillance to detect early-stage HCC is recommended for at-risk populations. Although ultrasonography (US) has been endorsed as the primary surveillance tool for HCC, a recent meta-analysis found that US has a sensitivity of 47% for detecting early-stage HCC, and its sensitivity for detecting early-stage HCC has been questioned. Many recent studies have explored the potential of alternative surveillance tools for HCC other than US, particularly for high-risk patients. Although complete gadoxetic acid-enhanced magnetic resonance imaging (MRI) demonstrated excellent performance, its high cost and long examination time can hamper its widespread adoption. Abbreviated MRI (AMRI) including hepatobiliary-phase imaging is a promising option to detect potential indicators of HCC, maintaining the benefits of highly sensitive imaging while reducing the examination time by omitting dynamic contrast-enhanced imaging. Because US is the current primary surveillance tool for HCC, this new surveillance tool must be compared with US in a prospective randomized comparative design. Thus, the hypothesis to be proved in this study is as follows: AMRI with gadoxetic acid will show a significantly higher detection rate compared to US for the detection of early-stage HCC in patients with cirrhosis and at high risk of developing HCC, defined as an estimated annual HCC risk of higher than 5%. We will also analyze whether the false-referral rate of AMRI with gadoxetic acid is not compromised by its high detection rate.

A total of 806 subjects will be randomized in a 1:1 ratio into the US group and the AMRI group. Subjects will be evaluated by two rounds of tests with US or AMRI at intervals of 6 months. After the completion of the two evaluation rounds, at least 6 months of clinical follow-up data will be collected to record the occurrence of interval cancer. US group: Subjects will be evaluated by two rounds of tests with abdominal US for the surveillance of HCC at intervals of 6 months. AMRI group: Subjects will be evaluated by two rounds of tests with AMRI with gadoxetic acid for the surveillance of HCC at intervals of 6 months.