To compare the diagnostic ability of gadolinium diethylene-triamine-pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA MRI) and contrast-enhanced ultrasound (CEUS) for the diagnosis of hepatocellular carcinoma (HCC) ≤3 cm in diameter in patients with hepatic cirrhosis or chronic hepatitis B.

Ninty-two cases with single focal liver lesion ≤3 cm who underwent CEUS and Gd-EOB-DTPA MRI in Southwest Hospital Affiliated to Third Military Medical University were enrolled in the study. And all cases were diagnosed with hepatic cirrhosis or chronic hepatitis B. Pathology was the golden standard and all cases were diagnosed pathologically by surgical operation. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy rate of the diagnosis of small HCC by CEUS, Gd-EOB-DTPA MRI and CEUS combined with Gd-EOB-DTPA MRI were calculated and compared with χ² test or Fisher exact probability.

Of the 92 cases, 82 cases were diagnosed as HCC and the other 10 cases were diagnosed as non-HCC. The sensitivity and the specificity for the diagnosis of HCC was 79.2% (65/82) and 70.0% (7/10) of CEUS alone and was comparable with that of Gd-EOB-DTPA MRI [74.4% (61/82) vs 70.0% (7/10)] alone (χ²=0.548, P=0.459; P=1.000). When both CEUS and Gd-EOB-DTPA MRI met the diagnostic criteria for HCC, the sensitivity was lower [61.0% (60/82), P=0.010] than that of CEUS alone, and the specificity [80.0% (8/10), P=1.000] was not statistically different from that of CEUS alone. When CEUS or Gd-EOB-DTPA MRI met the diagnostic criteria for HCC, the sensitivity [92.7% (76/82)] was higher than that of CEUS alone (χ²=6.119, P=0.013) or Gd-EOB-DTPA MRI alone (χ²=9.972, P=0.002), and the specificity [60.0% (6/10) ] was not statistically different from that of CEUS alone (P=1.000) or by Gd-EOB-DTPA MRI alone (P=1.000).

In patients with cirrhosis or chronic hepatitis B, the diagnostic ability of HCC≤ 3cm in diameter by CEUS alone was comparable to that by Gd-EOB-DTPA MRI alone. Combination of CEUS and Gd-EOB-DTPA MRI may increase the sensitivity for the diagnosis of HCC, but the specificity not statistically improved.