Evaluation of early-stage hepatocellular carcinoma by magnetic resonance imaging with gadoxetic acid detects additional lesions and increases overall survival

Background & Aims Hepatocellular carcinoma (HCC) has a high rate of intrahepatic recurrence after curative treatment, possibly because metastases are not always identified before treatment. Magnetic resonance (MR) imaging with a liver-specific contrast agent, gadoxetic acid, can detect small HCCs with high levels of sensitivity. We investigated whether MR imaging with gadoxetic acid increases overall and recurrence-free survival of patients initially assessed by computed tomography (CT). Methods We performed a retrospective study of data from 700 patients diagnosed with a single-nodular HCC by dynamic 4-phase CT in Seoul, Korea, from January 2009 through December 2010. Of these patients, 323 underwent additional evaluation with gadoxetic acid-enhanced MR imaging (CT+MR group). The 377 patients who did not undergo MR imaging analysis are referred to as the CT group. Results The CT and CT+MR groups were comparable in most baseline characteristics (Child-Pugh class A, 93.1% vs 94.7%; and median size of the primary HCCs, 2.8 vs 2.6 cm, respectively). Seventy-four additional HCC nodules were detected in 53 (16.4%) of the patients who underwent MR evaluation after CT (CT+MR group). These detections increased the Barcelona Clinic Liver Cancer stages for 43 patients (13.3%) and modified their treatment plans. On multivariable analyses, the CT+MR group had a significantly lower rate of HCC recurrence (hazard ratio [HR], 0.72; 95% confidence interval [CI], 0.54-0.96) and lower overall mortality (HR, 0.65; 95% CI, 0.44-0.96) than the CT group. In an analysis of 285 pairs of patients matched on the basis of the propensity score, the CT+MR group had significantly lower overall mortality (HR, 0.66; 95% CI, 0.44-0.99). Conclusions Among patients who underwent dynamic CT analysis of a single-nodular HCC, additional evaluation by MR imaging with gadoxetic acid led to the detection of additional HCC nodules in 16% of patients, reduced the risk of disease recurrence, and decreased overall mortality.