Detection of hypervascular hepatocellular carcinoma: comparison of SPIO-enhanced MRI with dynamic helical CT.

Objective: The purpose of this study was to compare the diagnostic performance of superparamagnetic iron oxide (SPIO)-enhanced MRI for the detection of hypervascular hepatocellular carcinoma (HCC) with dynamic helical CT.

Methods: SPIO-enhanced MR and dynamic helical CT images obtained from 41 patients with 52 hypervascular HCCs (5-130 mm; mean, 27 mm) were retrospectively analyzed. MRI were obtained with 1.5 T scanners using T2-weighted and proton density-weighted spin-echo (or fast spin-echo) sequences for all cases and a T2*-weighted gradient echo sequence for 36 cases. Four blinded observers reviewed images independently. Diagnostic accuracy was evaluated using alternative-free response receiver operating characteristic (AFROC) method. Sensitivities and positive predictive values (PPV) were also evaluated.

Results: The areas under the AFROC curves for each observer were greater for MR than for CT (means, 0.81 and 0.76; p < 0.05). The mean sensitivities for MR and CT were 0.75 and 0.71, respectively (p = 0.13). The mean PPVs were 0.83 and 0.79 (p = 0.21).

Conclusions: SPIO-enhanced MRI showed slightly better diagnostic performance than dynamic helical CT for the detection of hypervascular HCCs.